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2019 Volume 35 Issue 4
2019, 35(4): 569-579
doi: 10.11862/CJIC.2019.071
Abstract:
MnCo2O4/N-KB catalysts was prepared by hydrolysis-hydrothermal method, in which Mn(Ac)2 and Co(Ac)2 were used as precursors and nitrogen doped conductive carbon Ketjenblack (KB) was used as the carbon source. The microstructure of the MnCo2O4/N-KB catalysts and its catalytic performance for oxide reduction reaction were studied. The results showed that chemical coupling was formed between N-KB and MnCo2O4. It produced synergistic effect and effectively improved the oxygen reduction activity of MnCo2O4/N-KB catalyst. When the mass ratio of MnCo2O4 to N-KB was 1:9, the limiting current density of the reaction was 5.7 mA·cm-2 and the half wave potential was close to 0.81 V. MnCo2O4/N-KB catalyst obtained the best electrocatalytic performance for oxygen reduction. Comparing to the commercial Pt/C catatlyst with a current density of 5.2 mA·cm-2 and a half-wave potential 0.83 V, MnCo2O4/N-KB catalyst had a highly active oxygen reduction with higher ultimate current density and durability under the same capacity condition.
MnCo2O4/N-KB catalysts was prepared by hydrolysis-hydrothermal method, in which Mn(Ac)2 and Co(Ac)2 were used as precursors and nitrogen doped conductive carbon Ketjenblack (KB) was used as the carbon source. The microstructure of the MnCo2O4/N-KB catalysts and its catalytic performance for oxide reduction reaction were studied. The results showed that chemical coupling was formed between N-KB and MnCo2O4. It produced synergistic effect and effectively improved the oxygen reduction activity of MnCo2O4/N-KB catalyst. When the mass ratio of MnCo2O4 to N-KB was 1:9, the limiting current density of the reaction was 5.7 mA·cm-2 and the half wave potential was close to 0.81 V. MnCo2O4/N-KB catalyst obtained the best electrocatalytic performance for oxygen reduction. Comparing to the commercial Pt/C catatlyst with a current density of 5.2 mA·cm-2 and a half-wave potential 0.83 V, MnCo2O4/N-KB catalyst had a highly active oxygen reduction with higher ultimate current density and durability under the same capacity condition.
2019, 35(4): 580-588
doi: 10.11862/CJIC.2019.092
Abstract:
Cd-doped δ-Bi2O3 (Cd-δ-Bi2O3) were prepared by the alcoholic-hydrothermal method, and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and so on. The results showed that Cd-δ-Bi2O3 was assembled by 2D nanosheets. Cd in the form of Cd2+ was introduced in the lattice gap of δ-Bi2O3 and belonged to interstitial doping. Due to Cd doping, the band gap was decreased, the light-harvesting capability was enhanced, and the transmission and separation efficiency of carriers was improved. At room temperature and atmospheric pressure, the photocatalytic nitrogen fixation was investigated under visible light irradiation. The results showed that the photocatalytic nitrogen fixation rate of 6%Cd-δ-Bi2O3 with 3 h of light irradiation was 1.6 mmol·g-1·h-1·L-1, which was 10.67 times higher than that of δ-Bi2O3. The mechanism of photocatalytic N2 fixation was discussed by means of photocurrent and impedance. Doping Cd defect serves as the trap of photogenerated electrons, which delays the surface transfer of photogenerated electrons and enhances the chemisorption of target molecules.
Cd-doped δ-Bi2O3 (Cd-δ-Bi2O3) were prepared by the alcoholic-hydrothermal method, and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and so on. The results showed that Cd-δ-Bi2O3 was assembled by 2D nanosheets. Cd in the form of Cd2+ was introduced in the lattice gap of δ-Bi2O3 and belonged to interstitial doping. Due to Cd doping, the band gap was decreased, the light-harvesting capability was enhanced, and the transmission and separation efficiency of carriers was improved. At room temperature and atmospheric pressure, the photocatalytic nitrogen fixation was investigated under visible light irradiation. The results showed that the photocatalytic nitrogen fixation rate of 6%Cd-δ-Bi2O3 with 3 h of light irradiation was 1.6 mmol·g-1·h-1·L-1, which was 10.67 times higher than that of δ-Bi2O3. The mechanism of photocatalytic N2 fixation was discussed by means of photocurrent and impedance. Doping Cd defect serves as the trap of photogenerated electrons, which delays the surface transfer of photogenerated electrons and enhances the chemisorption of target molecules.
2019, 35(4): 589-597
doi: 10.11862/CJIC.2019.081
Abstract:
The composite cathode LaBiMn2O6-Sm0.2Ce0.8O1.9 (LBM-SDC) was prepared by glycine-nitrate combustion method. The phase and morphology evolution of the composite cathode were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that LBM had good chemical stability with SDC at 1 000℃. Due to the introduction of SDC, the length of the thriple-phase boundary was extended and the thermal matching between the cathode and the electrolyte was enhanced, resulting in an improvement in the electrochemical performance of the composite cathode. The electrochemical impedance spectrum (EIS) results indicated that the cathode polarization resistance (Rp) decreased steadily with the addition of SDC. The optimum addition of 30%(w/w) SDC in the composite cathode leads to the lowest Rp of 0.186 Ω·cm2 at 700℃ in air, which is 74% less than the pristine LBM cathode (RP=0.717 Ω·cm2). This is because an additional oxygen ion conduction path is generated after the introduction of SDC; thereby the oxygen reduction reaction is promoted. The maximum power density of the electrolyte-support single cell Ni-SDC/SDC/LBM-30%SDC reached 234 mW·cm-2 at 700℃. The power density maintains a stable value at 230 mW·cm-2 throughout a test period of 90 h, indicating that LBM-30%SDC had sufficient stability during the operation. The oxygen partial pressure measurement indicated that the oxygen molecule adsorption-diffusion process is the reaction rate-limiting step of the composite cathode.
The composite cathode LaBiMn2O6-Sm0.2Ce0.8O1.9 (LBM-SDC) was prepared by glycine-nitrate combustion method. The phase and morphology evolution of the composite cathode were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that LBM had good chemical stability with SDC at 1 000℃. Due to the introduction of SDC, the length of the thriple-phase boundary was extended and the thermal matching between the cathode and the electrolyte was enhanced, resulting in an improvement in the electrochemical performance of the composite cathode. The electrochemical impedance spectrum (EIS) results indicated that the cathode polarization resistance (Rp) decreased steadily with the addition of SDC. The optimum addition of 30%(w/w) SDC in the composite cathode leads to the lowest Rp of 0.186 Ω·cm2 at 700℃ in air, which is 74% less than the pristine LBM cathode (RP=0.717 Ω·cm2). This is because an additional oxygen ion conduction path is generated after the introduction of SDC; thereby the oxygen reduction reaction is promoted. The maximum power density of the electrolyte-support single cell Ni-SDC/SDC/LBM-30%SDC reached 234 mW·cm-2 at 700℃. The power density maintains a stable value at 230 mW·cm-2 throughout a test period of 90 h, indicating that LBM-30%SDC had sufficient stability during the operation. The oxygen partial pressure measurement indicated that the oxygen molecule adsorption-diffusion process is the reaction rate-limiting step of the composite cathode.
2019, 35(4): 598-604
doi: 10.11862/CJIC.2019.083
Abstract:
Di(p-chlorobenzy)tin 2-hydroxybenzoate with ladder-like framework[(μ3-O)(μ2-OH)(p-Cl-C6H4CH2Sn)2(O2CC6H4-OH-o)]2 (1) and triphenyltin 4-hydroxybenzoate (2) have been synthesized. The complexes were chara-cterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. Quantum chemical ab initio calculation as well as in vitro anticancer activity test have been carried out for the complexes. The results showed that complex 1 forms a structure containing Sn2O2 ladder-like skeleton and the complex 2 forms a nuclear tin structure. The tin atoms in the complexes all are five-coordinated with distorted trigonal bipyramid geometry. The antitumor activity showed that complexes 1 and 2 have higher activities than cisplatin to HT-29, HepG2, MCF-7, Hela and A549 cell line in vitro. Their thermal stabilities were further investigated, and the results showed that complexes 1 and 2 were stable below 90℃ and below 120℃, respectively.
Di(p-chlorobenzy)tin 2-hydroxybenzoate with ladder-like framework[(μ3-O)(μ2-OH)(p-Cl-C6H4CH2Sn)2(O2CC6H4-OH-o)]2 (1) and triphenyltin 4-hydroxybenzoate (2) have been synthesized. The complexes were chara-cterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. Quantum chemical ab initio calculation as well as in vitro anticancer activity test have been carried out for the complexes. The results showed that complex 1 forms a structure containing Sn2O2 ladder-like skeleton and the complex 2 forms a nuclear tin structure. The tin atoms in the complexes all are five-coordinated with distorted trigonal bipyramid geometry. The antitumor activity showed that complexes 1 and 2 have higher activities than cisplatin to HT-29, HepG2, MCF-7, Hela and A549 cell line in vitro. Their thermal stabilities were further investigated, and the results showed that complexes 1 and 2 were stable below 90℃ and below 120℃, respectively.
2019, 35(4): 605-612
doi: 10.11862/CJIC.2019.069
Abstract:
Three transition metal coordination polymer materials were successfully synthesized by solvothermal method with the main ligand 2, 5-pyridinedicarboxylic acid (H2L1) or thiophene 2, 5-dicarboxylic acid (H2L2), and co-ligand 4, 4'-bipyridyl (4, 4'-bipy) or 1, 10-phenanthroline (phen). The complexes were characterized by X-ray single crystal diffraction, infrared spectroscopy (IR), fluorescence spectroscopy (FL) and thermogravimetric analysis (TG/DTG). The analysis of single crystal structure shows that all complexes belong to monoclinic system. Complexes 1 and 2 crystalize in P1 space group, and complex 3 crystalizes in P2/n. Complex 1 and complex 3 are zero-dimensional dinuclear small molecules, and complex 2 has a two-dimensional network structure.
Three transition metal coordination polymer materials were successfully synthesized by solvothermal method with the main ligand 2, 5-pyridinedicarboxylic acid (H2L1) or thiophene 2, 5-dicarboxylic acid (H2L2), and co-ligand 4, 4'-bipyridyl (4, 4'-bipy) or 1, 10-phenanthroline (phen). The complexes were characterized by X-ray single crystal diffraction, infrared spectroscopy (IR), fluorescence spectroscopy (FL) and thermogravimetric analysis (TG/DTG). The analysis of single crystal structure shows that all complexes belong to monoclinic system. Complexes 1 and 2 crystalize in P1 space group, and complex 3 crystalizes in P2/n. Complex 1 and complex 3 are zero-dimensional dinuclear small molecules, and complex 2 has a two-dimensional network structure.
2019, 35(4): 613-620
doi: 10.11862/CJIC.2019.088
Abstract:
n-Type porous silicon were prepared by metal-assisted chemical etching (MACE) and then the porous Si/TiO2 nanowires photoanodes were prepared by hydrothermal synthesis. Samples were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that the macrospore size of the porous Si increases from about 0.1 to 0.4 μm with the increasing of etching time. Porous Si/TiO2 nanowires corresponded primarily to rutile phase and slight traces of anatase. The results showed that porous Si/TiO2 nanowires sample with etching for 35 min had the highest anti-reflectivity the corresponding photoanode showed the best photocurrent (photocurrent density) under simulated solar light. In addition, the photoelectric catalysis results showed that porous Si/TiO2 nanowires with etching for 35 min at 1.5 V showed the best catalytic activities, which is attributed to the anti-reflection, heterogeneous effect and window effect.
n-Type porous silicon were prepared by metal-assisted chemical etching (MACE) and then the porous Si/TiO2 nanowires photoanodes were prepared by hydrothermal synthesis. Samples were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that the macrospore size of the porous Si increases from about 0.1 to 0.4 μm with the increasing of etching time. Porous Si/TiO2 nanowires corresponded primarily to rutile phase and slight traces of anatase. The results showed that porous Si/TiO2 nanowires sample with etching for 35 min had the highest anti-reflectivity the corresponding photoanode showed the best photocurrent (photocurrent density) under simulated solar light. In addition, the photoelectric catalysis results showed that porous Si/TiO2 nanowires with etching for 35 min at 1.5 V showed the best catalytic activities, which is attributed to the anti-reflection, heterogeneous effect and window effect.
2019, 35(4): 621-628
doi: 10.11862/CJIC.2019.076
Abstract:
The nanostructured Mg3Si4O10(OH)2 in situ grown on diatomite were first synthesized via a hydrothermal route. Moreover, Mg(OH)2 nanoflowers were first grown on the surface of diatomite after hydrothermal treatment for 0.5~2 h, these nanoflowers obtained the surface areas of 180 m2·g-1. As the hydrothermal reaction time increasing to 3 h, the Mg(OH)2 nanoflowers were completely transformed to lattice-like structure Mg3Si4O10(OH)2 which possessed the higher surface area of 350 m2·g-1. Mg3Si4O10(OH)2/diatomite composite structure showed a well adsorption performance of 570 mg·g-1 for Cr(Ⅵ). It is firmly believed that the adsorbent has a great significance of removing heavy metal ions in wastewater.
The nanostructured Mg3Si4O10(OH)2 in situ grown on diatomite were first synthesized via a hydrothermal route. Moreover, Mg(OH)2 nanoflowers were first grown on the surface of diatomite after hydrothermal treatment for 0.5~2 h, these nanoflowers obtained the surface areas of 180 m2·g-1. As the hydrothermal reaction time increasing to 3 h, the Mg(OH)2 nanoflowers were completely transformed to lattice-like structure Mg3Si4O10(OH)2 which possessed the higher surface area of 350 m2·g-1. Mg3Si4O10(OH)2/diatomite composite structure showed a well adsorption performance of 570 mg·g-1 for Cr(Ⅵ). It is firmly believed that the adsorbent has a great significance of removing heavy metal ions in wastewater.
2019, 35(4): 629-634
doi: 10.11862/CJIC.2019.080
Abstract:
The TiSAPO-34 molecular sieves have been successfully synthesized via a facile hydrothermal method. Scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), N2 adsorption-desorption, UV-Vis diffuse reflectance spectra (UV-Vis DRS) and thermogravimetric (TG) have been employed to determine the properties of the samples. The TiSAPO-34 molecular sieves could be served as efficient adsorbents for adsorbing a typical contaminants, methylene blue (MB) from water. Moreover, the doped amount of titanium, the stability and recyclability of the catalysts have been investigated in detail. The results revealed that the resulting samples were the spherical microporous molecular sieve, which with good thermal stability. Interestingly, a certain amount of Ti atoms could embed the matrix of SAPO-34 molecular sieves successfully, and the skeleton structure of SAPO-34 molecular sieves still maintained. Importantly, the samples synthetic after crystallization at 190℃ for 24 h exhibited the optimal adsorption performance for the adsorption of MB, giving an adsorption rate of 80% after 1 hour.
The TiSAPO-34 molecular sieves have been successfully synthesized via a facile hydrothermal method. Scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), N2 adsorption-desorption, UV-Vis diffuse reflectance spectra (UV-Vis DRS) and thermogravimetric (TG) have been employed to determine the properties of the samples. The TiSAPO-34 molecular sieves could be served as efficient adsorbents for adsorbing a typical contaminants, methylene blue (MB) from water. Moreover, the doped amount of titanium, the stability and recyclability of the catalysts have been investigated in detail. The results revealed that the resulting samples were the spherical microporous molecular sieve, which with good thermal stability. Interestingly, a certain amount of Ti atoms could embed the matrix of SAPO-34 molecular sieves successfully, and the skeleton structure of SAPO-34 molecular sieves still maintained. Importantly, the samples synthetic after crystallization at 190℃ for 24 h exhibited the optimal adsorption performance for the adsorption of MB, giving an adsorption rate of 80% after 1 hour.
2019, 35(4): 635-642
doi: 10.11862/CJIC.2019.079
Abstract:
The metal organic framework compounds MIL-125(Ti) and NH2-MIL-125(Ti) were prepared and chara-cterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR)and specific surface area (BET). The humidity sensing performances of the two materials based QCM sensors were studied by exposed to humidity range of 11%~97%RH (relative humidity). The experimental results show that the MIL-125(Ti) and NH2-MIL-125(Ti) sensors have some advantages, such as high sensitivity, good repeatability, fast response/recovery and etc. Compared with MIL-125(Ti), the sensor modified by NH2-MIL-125(Ti) exhibited higher response to humidity.when the indoor humidity was about 52%, the frequency shift of the NH2-MIL-125(Ti) sensor to a 11% relative humidity was 57 Hz higher than MIL-125(Ti), indicating that the amino-functionalized material had a certain enhancement to the response of the humidity sensor. Furthermore, the adsorption enthalpys between water molecules and MIL-125(Ti) or NH2-MIL-125(Ti) was obtained by Materials Studio, which proved that the amino functionalization could enhance the humidity sensitivity of MIL-125(Ti).
The metal organic framework compounds MIL-125(Ti) and NH2-MIL-125(Ti) were prepared and chara-cterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR)and specific surface area (BET). The humidity sensing performances of the two materials based QCM sensors were studied by exposed to humidity range of 11%~97%RH (relative humidity). The experimental results show that the MIL-125(Ti) and NH2-MIL-125(Ti) sensors have some advantages, such as high sensitivity, good repeatability, fast response/recovery and etc. Compared with MIL-125(Ti), the sensor modified by NH2-MIL-125(Ti) exhibited higher response to humidity.when the indoor humidity was about 52%, the frequency shift of the NH2-MIL-125(Ti) sensor to a 11% relative humidity was 57 Hz higher than MIL-125(Ti), indicating that the amino-functionalized material had a certain enhancement to the response of the humidity sensor. Furthermore, the adsorption enthalpys between water molecules and MIL-125(Ti) or NH2-MIL-125(Ti) was obtained by Materials Studio, which proved that the amino functionalization could enhance the humidity sensitivity of MIL-125(Ti).
2019, 35(4): 643-648
doi: 10.11862/CJIC.2019.072
Abstract:
A porous flower-like hydroxyapatite/silver (HA/Ag) nanocomposite was prepared via one-pot sol-thernal method. The unique Raman-enhancing effect of the HA/Ag nanocomposite as the surface-enhanced Raman scattering (SERS) active substrate was revealed by rhodamine B detection at the concentration as low as 10-8 mol·L-1. In the detection, changing the intensity of the Raman laser and the position of the taking points can effectively improve the sensitivity of the detection. In addition, the prepared porous nanocomposite HA/Ag acts as a catalyst for the reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP), which can greatly shorten the reaction time by 40 min.
A porous flower-like hydroxyapatite/silver (HA/Ag) nanocomposite was prepared via one-pot sol-thernal method. The unique Raman-enhancing effect of the HA/Ag nanocomposite as the surface-enhanced Raman scattering (SERS) active substrate was revealed by rhodamine B detection at the concentration as low as 10-8 mol·L-1. In the detection, changing the intensity of the Raman laser and the position of the taking points can effectively improve the sensitivity of the detection. In addition, the prepared porous nanocomposite HA/Ag acts as a catalyst for the reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP), which can greatly shorten the reaction time by 40 min.
2019, 35(4): 649-657
doi: 10.11862/CJIC.2019.089
Abstract:
A fluorescence probe 2 containing 4-hydroxystyryl at the 3-position on the boron fluoride dipyrromethene(BODIPY) fluorophore was successfully synthesized in high yield using the 4-formylphenyl picolinate as the starting material instead of 4-hydroxybenzaldehyde. Probe 2 exhibits excellent optical performance, including good solubility, high extinction coefficient and high fluorescence quantum yield (Ф=0.90 in CH3OH). The absorption and emission bands of probe 2 are centered at 570 and 585 nm in CH3OH, respectively. When the pH value of the solution changes from acidity to basicity, both positive fluorescence response and visual color change make naked-eye detection of pH value possible due to the deprotonation of hydroxyl group. With the addition of Fe3+ ions into the solution, visual color changes and blue shift of the absorption and fluorescence peak were detected as well. Hence, the probe 2 could also be used as a ratiometric fluorescent probe for selectively monitoring Fe3+ ion in solution and in living cells.
A fluorescence probe 2 containing 4-hydroxystyryl at the 3-position on the boron fluoride dipyrromethene(BODIPY) fluorophore was successfully synthesized in high yield using the 4-formylphenyl picolinate as the starting material instead of 4-hydroxybenzaldehyde. Probe 2 exhibits excellent optical performance, including good solubility, high extinction coefficient and high fluorescence quantum yield (Ф=0.90 in CH3OH). The absorption and emission bands of probe 2 are centered at 570 and 585 nm in CH3OH, respectively. When the pH value of the solution changes from acidity to basicity, both positive fluorescence response and visual color change make naked-eye detection of pH value possible due to the deprotonation of hydroxyl group. With the addition of Fe3+ ions into the solution, visual color changes and blue shift of the absorption and fluorescence peak were detected as well. Hence, the probe 2 could also be used as a ratiometric fluorescent probe for selectively monitoring Fe3+ ion in solution and in living cells.
2019, 35(4): 658-666
doi: 10.11862/CJIC.2019.078
Abstract:
In order to improve the ability to remove 2-nitro-1, 3-benzenediol (NRC) in water, Fe3O4/GO/PPy ternary composites were prepared by hydrothermal method using GO prepared by modified Hummers method. UV-visible absorption spectroscopy (UV-Vis), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ζ potential analysis to study the structural of magnetic nanocomposites, while the pH value of the solution, the amount of adsorbent, initial concentration, adsorption time and temperature on the adsorption of NRC were studied by adsorption kinetics and adsorption isotherms. The results showed that the prepared Fe3O4/GO/PPy composites were layered dispersed structure; GO layer structure was stripped; PPy and Fe3O4 particles irregularly interspersed among the GO sheets. Fe3O4 particles were the polyhedral crystal structure with polyhedral size in the range of 100~300 nm. The interface between Fe3O4 and PPy particles in the graphene sheet layer was in close contact with each other; Fe3O4/GO/PPy could easily separated in water because of the superparamagnetism. Fe3O4/GO/PPy could be separated with 40 s under external magnetic field and the removal ratio of the NRC was 91.6%. The adsorption property of Fe3O4/GO/PPy for NRC obtained the strongest adsorption under the NRC initial concentration (C0) was 200 mg·L-1, pH value was 5.00±0.05, tempreture (T) was 318.15 K, adsorbent dosage (m) was 10 mg·L-1 and time (t) was 6 h, and the adsorption amount reached 163.3 mg·g-1. The adsorption kinetics of NRC follows the second-order kinetic model, and the adsorption isotherm conforms to the Langmuir model. After using NRC for five times, the removal rate decreased from 91.6% to 77.6%, that illustrated Fe3O4/GO/PPy magnetic complex possessed good stability and repeated use ability.
In order to improve the ability to remove 2-nitro-1, 3-benzenediol (NRC) in water, Fe3O4/GO/PPy ternary composites were prepared by hydrothermal method using GO prepared by modified Hummers method. UV-visible absorption spectroscopy (UV-Vis), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ζ potential analysis to study the structural of magnetic nanocomposites, while the pH value of the solution, the amount of adsorbent, initial concentration, adsorption time and temperature on the adsorption of NRC were studied by adsorption kinetics and adsorption isotherms. The results showed that the prepared Fe3O4/GO/PPy composites were layered dispersed structure; GO layer structure was stripped; PPy and Fe3O4 particles irregularly interspersed among the GO sheets. Fe3O4 particles were the polyhedral crystal structure with polyhedral size in the range of 100~300 nm. The interface between Fe3O4 and PPy particles in the graphene sheet layer was in close contact with each other; Fe3O4/GO/PPy could easily separated in water because of the superparamagnetism. Fe3O4/GO/PPy could be separated with 40 s under external magnetic field and the removal ratio of the NRC was 91.6%. The adsorption property of Fe3O4/GO/PPy for NRC obtained the strongest adsorption under the NRC initial concentration (C0) was 200 mg·L-1, pH value was 5.00±0.05, tempreture (T) was 318.15 K, adsorbent dosage (m) was 10 mg·L-1 and time (t) was 6 h, and the adsorption amount reached 163.3 mg·g-1. The adsorption kinetics of NRC follows the second-order kinetic model, and the adsorption isotherm conforms to the Langmuir model. After using NRC for five times, the removal rate decreased from 91.6% to 77.6%, that illustrated Fe3O4/GO/PPy magnetic complex possessed good stability and repeated use ability.
2019, 35(4): 667-673
doi: 10.11862/CJIC.2019.082
Abstract:
In order to enhance the electrochemical energy storage properties of LiNi0.8Co0.15Al0.05O2 (NCA) cathode material, polyvinylpyrrolidone (PVP) was added in to modify the NCA morphology during the NCA preparation process and thus enhanced its electrochemical performance. A two-step co-precipitation method was used to prepare NCA precursors. With continuous stirring, solution A (0.2 mol·L-1 CoSO4) was slowly added into solution C (0.3 mol·L-1 H2C2O4 and PVP, the mass ratio of the PVP to all metal oxides was 1.64%(w/w)) to form a suspension. After that, solution B (0.32 mol·L-1 NiSO4, 0.053 mol·L-1 CoSO4 and 0.01 mol·L-1 Al2(SO4)3) was added into the suspension drop by drop, and then the solution was stirred for 2 hours and filtered. The obtained solid object was washed and dried in vacuum at 80℃ for 12 hours. The obtained sample was marked as MC2O4·2H2O-PVA. The obtained sample mentioned above was mixed thoroughly with LiOH·H2O at a molar ratio of 1:1.02. Then, the mixture was operated as the following steps:calcined at 500℃ for 5 h in air atmosphere, and then cooled to ambient temperature to grind for half an hour, after that sintered at 800℃ for 12 h in O2 atmosphere. The obtained sample was named as NCA-PVP. The morphology and structure of the obtained samples were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical performances were characterized by electrochemical workstation and cell tester with assembling into button battery. The results showed that the NCA material modified by PVP had a more complete rod-like structure, a better layered structure and a better electrochemical energy storage property due to the PVP space and electrostatic effects. The initial discharge specific capacity and charge-discharge efficiency of the sample at 0.1C has increased from 143.36 mAh·g-1 and 78.25% to 170.24 mAh·g-1 and 89.20%, respectively. The capacity retention rate was 94.28% after 50 cycles at 0.2C.
In order to enhance the electrochemical energy storage properties of LiNi0.8Co0.15Al0.05O2 (NCA) cathode material, polyvinylpyrrolidone (PVP) was added in to modify the NCA morphology during the NCA preparation process and thus enhanced its electrochemical performance. A two-step co-precipitation method was used to prepare NCA precursors. With continuous stirring, solution A (0.2 mol·L-1 CoSO4) was slowly added into solution C (0.3 mol·L-1 H2C2O4 and PVP, the mass ratio of the PVP to all metal oxides was 1.64%(w/w)) to form a suspension. After that, solution B (0.32 mol·L-1 NiSO4, 0.053 mol·L-1 CoSO4 and 0.01 mol·L-1 Al2(SO4)3) was added into the suspension drop by drop, and then the solution was stirred for 2 hours and filtered. The obtained solid object was washed and dried in vacuum at 80℃ for 12 hours. The obtained sample was marked as MC2O4·2H2O-PVA. The obtained sample mentioned above was mixed thoroughly with LiOH·H2O at a molar ratio of 1:1.02. Then, the mixture was operated as the following steps:calcined at 500℃ for 5 h in air atmosphere, and then cooled to ambient temperature to grind for half an hour, after that sintered at 800℃ for 12 h in O2 atmosphere. The obtained sample was named as NCA-PVP. The morphology and structure of the obtained samples were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical performances were characterized by electrochemical workstation and cell tester with assembling into button battery. The results showed that the NCA material modified by PVP had a more complete rod-like structure, a better layered structure and a better electrochemical energy storage property due to the PVP space and electrostatic effects. The initial discharge specific capacity and charge-discharge efficiency of the sample at 0.1C has increased from 143.36 mAh·g-1 and 78.25% to 170.24 mAh·g-1 and 89.20%, respectively. The capacity retention rate was 94.28% after 50 cycles at 0.2C.
2019, 35(4): 674-686
doi: 10.11862/CJIC.2019.077
Abstract:
The metal-free carbon materials were obtained by a facile KOH activation and pyrolysis process from inexpensive and readily available pomelo peels, and possessed honeycomb-like nanostructures with a high specific surface area of 1 055 m2·g-1 and a high graphitization degree. A porous activated carbon (PAC) material modified electrode was utilized as the working electrode for the simultaneous detection of Cd2+, Pb2+, and Cu2+ using square-wave anodic stripping voltammetry (SWASV) and exhibited high sensitivity, repeatability, stability and a low detection limit. The interconnected micropores and mesopores act as efficient ion-transfer channels and provid active surface areas with high accessibility, which serve as transport highways to accelerate mass diffusion and significantly promote exchange efficiency. High graphitization degree increases the electrical conductivity of the material and accelerates electron transport.
The metal-free carbon materials were obtained by a facile KOH activation and pyrolysis process from inexpensive and readily available pomelo peels, and possessed honeycomb-like nanostructures with a high specific surface area of 1 055 m2·g-1 and a high graphitization degree. A porous activated carbon (PAC) material modified electrode was utilized as the working electrode for the simultaneous detection of Cd2+, Pb2+, and Cu2+ using square-wave anodic stripping voltammetry (SWASV) and exhibited high sensitivity, repeatability, stability and a low detection limit. The interconnected micropores and mesopores act as efficient ion-transfer channels and provid active surface areas with high accessibility, which serve as transport highways to accelerate mass diffusion and significantly promote exchange efficiency. High graphitization degree increases the electrical conductivity of the material and accelerates electron transport.
2019, 35(4): 687-694
doi: 10.11862/CJIC.2019.084
Abstract:
In the presence of different N ancillary ligands, treatment of H2MPCA with corresponding Pb(Ⅱ) salts afforded two complexes, [Pb(HMPCA)2(H2O)2]·H2O (1) and[Pb(HMPCA)2(phen)]·H2O (2) (H2MPCA=5-methyl-1H-pyrazole-3-carboxylic acid, phen=1, 10-phenanthroline). In dinuclear complex 1, the[Pb(μ2-HMPCA))]2 units are extended into a 1D chain structure by a pair of Pb…O secondary bonds. Then, these 1D chains are further assembled to a 2D supramolecular structure through intermolecular hydrogen bonds. While complex 2 displays a mononuclear structure, the Pb…O secondary bonds emerged in the Pb2O2 rhomb, which are further packed into a 3D supramolecular framework though π…π interactions and hydrogen bonds. The thermal and luminescent properties of complexes 1 and 2 have also been investigated.
In the presence of different N ancillary ligands, treatment of H2MPCA with corresponding Pb(Ⅱ) salts afforded two complexes, [Pb(HMPCA)2(H2O)2]·H2O (1) and[Pb(HMPCA)2(phen)]·H2O (2) (H2MPCA=5-methyl-1H-pyrazole-3-carboxylic acid, phen=1, 10-phenanthroline). In dinuclear complex 1, the[Pb(μ2-HMPCA))]2 units are extended into a 1D chain structure by a pair of Pb…O secondary bonds. Then, these 1D chains are further assembled to a 2D supramolecular structure through intermolecular hydrogen bonds. While complex 2 displays a mononuclear structure, the Pb…O secondary bonds emerged in the Pb2O2 rhomb, which are further packed into a 3D supramolecular framework though π…π interactions and hydrogen bonds. The thermal and luminescent properties of complexes 1 and 2 have also been investigated.
2019, 35(4): 695-702
doi: 10.11862/CJIC.2019.074
Abstract:
F-doped BiVO4 photocatalysts were fabricated by using a simple one-step alcohol-hydrothermal method with NH4F as the precursor of the dopant. The physicochemical properties of the photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis), and photoluminescence spectra (PL). Their photocatalytic activities were determined through the degradation of phenol in the presence of a small amount of H2O2 under visible-light illumination. It is found that compared to the un-doped BiVO4 sample, the F-doped BiVO4 samples retained the monoclinic structure and had higher crystallinity, surface oxygen vacancy densities and separation efficiency of photogenerated charge carriers, stronger optical absorbance performances, and lower bandgap energies. Among these F-doped BiVO4 samples, the F-doped BiVO4 sample (nominal nF/nBi=1.0, bandgap energy=2.43 eV) exhibited the best photocatalytic performance (the conversion of phenol up to 95% in 90 min), due to the highest crystallinity, surface oxygen vacancy density, and separation efficiency of photogenerated charge carriers, the strongest optical absorbance performance, and the lowest bandgap energy.
F-doped BiVO4 photocatalysts were fabricated by using a simple one-step alcohol-hydrothermal method with NH4F as the precursor of the dopant. The physicochemical properties of the photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis), and photoluminescence spectra (PL). Their photocatalytic activities were determined through the degradation of phenol in the presence of a small amount of H2O2 under visible-light illumination. It is found that compared to the un-doped BiVO4 sample, the F-doped BiVO4 samples retained the monoclinic structure and had higher crystallinity, surface oxygen vacancy densities and separation efficiency of photogenerated charge carriers, stronger optical absorbance performances, and lower bandgap energies. Among these F-doped BiVO4 samples, the F-doped BiVO4 sample (nominal nF/nBi=1.0, bandgap energy=2.43 eV) exhibited the best photocatalytic performance (the conversion of phenol up to 95% in 90 min), due to the highest crystallinity, surface oxygen vacancy density, and separation efficiency of photogenerated charge carriers, the strongest optical absorbance performance, and the lowest bandgap energy.
2019, 35(4): 703-710
doi: 10.11862/CJIC.2019.075
Abstract:
Two coordination polymers[Zn(Athy)Br]n (1, HAthy=5-amino-1H-1, 2, 4-triazol-3-ol) and[Mn(Atca)2(H2O)2] (2, HAtca=5-amino-1H-1, 2, 4-triazole-3-carboxylic acid) were separately synthesized by hydrothermal method and solution diffusion method using HAtca, ZnBr2 and MnCl2, respectively. X-ray single crystal diffraction analyses indicate both 1 and 2 have different crystal structures. Complex 1 crystallizes in the orthorhombic system, space group Pbca. Complex 2 crystallizes in the monoclinic system, space group P21/c. Complex 1 is a 2D grid structure without any hydrogen bonds, but complex 2 has a 3D grid structure constructed by highly stable hydrogen bonds. Moreover, 1 and 2 show strong fluorescence emission at 360, 462 nm and 382, 402 nm at room temperature, respectively.
Two coordination polymers[Zn(Athy)Br]n (1, HAthy=5-amino-1H-1, 2, 4-triazol-3-ol) and[Mn(Atca)2(H2O)2] (2, HAtca=5-amino-1H-1, 2, 4-triazole-3-carboxylic acid) were separately synthesized by hydrothermal method and solution diffusion method using HAtca, ZnBr2 and MnCl2, respectively. X-ray single crystal diffraction analyses indicate both 1 and 2 have different crystal structures. Complex 1 crystallizes in the orthorhombic system, space group Pbca. Complex 2 crystallizes in the monoclinic system, space group P21/c. Complex 1 is a 2D grid structure without any hydrogen bonds, but complex 2 has a 3D grid structure constructed by highly stable hydrogen bonds. Moreover, 1 and 2 show strong fluorescence emission at 360, 462 nm and 382, 402 nm at room temperature, respectively.
2019, 35(4): 711-719
doi: 10.11862/CJIC.2019.070
Abstract:
PbF2:Er3+, Yb3+ bidirectional conversion phosphors were successful prepared by the high temperature solid-state reaction method. The samples were characterized by X-ray powder diffraction (XRD), general structure analysis system structure refinement, the intensity-power test and fluorescence spectrum method. XRD and Rietveld refinement were performed to analyze the phase composition and the changes of cell parameters. The fluorescence spectra analysis showed the samples exhibited the intense green emissions in the range of 540~550 nm and weak red emission in the range of 650~660 nm when excited at ultraviolet (378 nm) and different infrared wavelengths (808, 980, 1 064 and 1 550 nm). Finally, luminescence mechanisms excited at different infrared wavelengths were discussed by means of the intensity-power test, and the down-conversion (DC) luminescence mechanism excited at 378 nm was analyzed.
PbF2:Er3+, Yb3+ bidirectional conversion phosphors were successful prepared by the high temperature solid-state reaction method. The samples were characterized by X-ray powder diffraction (XRD), general structure analysis system structure refinement, the intensity-power test and fluorescence spectrum method. XRD and Rietveld refinement were performed to analyze the phase composition and the changes of cell parameters. The fluorescence spectra analysis showed the samples exhibited the intense green emissions in the range of 540~550 nm and weak red emission in the range of 650~660 nm when excited at ultraviolet (378 nm) and different infrared wavelengths (808, 980, 1 064 and 1 550 nm). Finally, luminescence mechanisms excited at different infrared wavelengths were discussed by means of the intensity-power test, and the down-conversion (DC) luminescence mechanism excited at 378 nm was analyzed.
2019, 35(4): 720-728
doi: 10.11862/CJIC.2019.059
Abstract:
Two novel copper(Ⅰ) complexes[Cu(dppBz)(dpq)]ClO4 (1) and[Cu(dppe)(dpq)]ClO4 (2) (dppBz=1, 2-bis(diphenylphosphino)benzene, dppe=1, 2-bis(diphenylphosphino)ethene, dpq=[2, 3-f]pyrazino[1 , 10 ]phenanthroline) have been synthesized and characterized by X-ray diffraction, elemental analysis, infrared spectroscopy, absorption spectra, luminescent spectra, 1H NMR, 31P NMR spectroscopy and terahertz (THz) time-domain absorption spectroscopy. The central Cu(Ⅰ) ion is chelated by a diimine ligand and a diphosphine ligand forming a distorted tetrahedron configuration for 1, and the configuration of 2 is similar to 1. The luminescent spectra of 2 indicated that the emission has metal-to-ligand charge transfer (MLCT) characteristics. The terahertz time-domain absorption spectroscopy analysis in a range of 0.2~2.8 THz showed that the absorption peaks at 0.40~0.90 THz are related to the coordination of the central Cu(Ⅰ).
Two novel copper(Ⅰ) complexes[Cu(dppBz)(dpq)]ClO4 (1) and[Cu(dppe)(dpq)]ClO4 (2) (dppBz=1, 2-bis(diphenylphosphino)benzene, dppe=1, 2-bis(diphenylphosphino)ethene, dpq=[2, 3-f]pyrazino[
2019, 35(4): 729-736
doi: 10.11862/CJIC.2019.073
Abstract:
A non-enzymatic glucose biosensor was designed for the first time based on the employment of monodisperse Ni12P5 nanoparticles (NPs), which were fabricated by a modified one-pot hot-solution colloidal preparation method. The crystal structure, chemical composition and morphology of the Ni12P5 NPs was determined by using power X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectra, X-ray energy dispersive spectrometer. The developed sensor has presented excellent performance which involved a quick response time less than 3 s, a broad detection ranging from 0.002 to 4.2 mmol·L-1, a high sensitivity up to 1 572 mA·L·mol-1·cm-2, and a detection limit as low as 0.8 μmol·L-1. Additionally, it can be used to detect the glucose in the human blood serum with satisfactory result.
A non-enzymatic glucose biosensor was designed for the first time based on the employment of monodisperse Ni12P5 nanoparticles (NPs), which were fabricated by a modified one-pot hot-solution colloidal preparation method. The crystal structure, chemical composition and morphology of the Ni12P5 NPs was determined by using power X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectra, X-ray energy dispersive spectrometer. The developed sensor has presented excellent performance which involved a quick response time less than 3 s, a broad detection ranging from 0.002 to 4.2 mmol·L-1, a high sensitivity up to 1 572 mA·L·mol-1·cm-2, and a detection limit as low as 0.8 μmol·L-1. Additionally, it can be used to detect the glucose in the human blood serum with satisfactory result.
2019, 35(4): 737-744
doi: 10.11862/CJIC.2019.091
Abstract:
An aminoantipyrine based chemosensor, (E)-1, 5-dimethyl-4-((2-(4-methylpyridin-2-yl)pyridin-4-yl)methyleneamino)-2-phenyl-1, 2-dihydropyrazol-3-one(L), derived from 4-aminoantipyrine and 2-(4-methylpyridin-2-yl) isonicotinaldehyde, was synthesized and the optical and metal sensing properties were investigated. The chemosensor L showed a selective colorimetric sensing ability for Fe2+ by changing colors from pale yellow to deep red in water-ethanol (9:1, V/V) medium, which facilitates the 'naked-eye' recognition of Fe2+ from other examined metal ions. The complex stoichiometry of Fe2+ to L(1:3, [FeL3]2+) was obtained by Job's method. The association constant was determined to be 3.70×1021 L3·mol-3. The present results indicate that the chemosensor L could be used as a selective, sensitive colorimetric sensor for Fe2+.
An aminoantipyrine based chemosensor, (E)-1, 5-dimethyl-4-((2-(4-methylpyridin-2-yl)pyridin-4-yl)methyleneamino)-2-phenyl-1, 2-dihydropyrazol-3-one(L), derived from 4-aminoantipyrine and 2-(4-methylpyridin-2-yl) isonicotinaldehyde, was synthesized and the optical and metal sensing properties were investigated. The chemosensor L showed a selective colorimetric sensing ability for Fe2+ by changing colors from pale yellow to deep red in water-ethanol (9:1, V/V) medium, which facilitates the 'naked-eye' recognition of Fe2+ from other examined metal ions. The complex stoichiometry of Fe2+ to L(1:3, [FeL3]2+) was obtained by Job's method. The association constant was determined to be 3.70×1021 L3·mol-3. The present results indicate that the chemosensor L could be used as a selective, sensitive colorimetric sensor for Fe2+.
2019, 35(4): 745-751
doi: 10.11862/CJIC.2019.085
Abstract:
Two novel complexes, [Ga(L)2]NO3·4CH3OH (1) and[In(L)2]NO3·1.75CH3OH (2) based on HL (HL=3-ethyl-2-acetylpyrazine N(4)-(p-tolyl)thiosemicarbazone) were synthesized and characterized by X-ray diffraction analyses. Complexes 1 and 2 are isostructural and crystallize in the monoclinic system, space group P21/c with different crystal methanol molecules. The metal center in each complex is surrounded by two monoanionic L- with[N2S] donor set, thus giving a distorted octahedral coordination geometry. In addition, the fluorescence spectra indicate that the interactions of complexes with DNA are stronger than that of ligand HL.
Two novel complexes, [Ga(L)2]NO3·4CH3OH (1) and[In(L)2]NO3·1.75CH3OH (2) based on HL (HL=3-ethyl-2-acetylpyrazine N(4)-(p-tolyl)thiosemicarbazone) were synthesized and characterized by X-ray diffraction analyses. Complexes 1 and 2 are isostructural and crystallize in the monoclinic system, space group P21/c with different crystal methanol molecules. The metal center in each complex is surrounded by two monoanionic L- with[N2S] donor set, thus giving a distorted octahedral coordination geometry. In addition, the fluorescence spectra indicate that the interactions of complexes with DNA are stronger than that of ligand HL.
