【无机化学学报】doi: 10.11862/CJIC.20240255
采用原位聚合法制备了氯氧化铋(BiOCl)与聚苯胺(PANI)复合的Ⅱ型异质结光催化剂BiOCl/PANI,并采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UV-Vis DRS)和N2吸附-脱附测试等多种技术手段对其进行了表征,考察了BiOCl/PANI在模拟可见光下对罗丹明B (RhB)的光催化降解性能。实验结果表明:BiOCl/PANI催化剂比PANI和BiOCl具有更高的光催化活性,在RhB质量浓度为50 mg·L-1、PANI与BiOCl的物质的量之比为0.02∶1、50 mg·L-1的催化剂条件下,所制备的BiOCl/PANI光催化150 min后,RhB降解率为98.8%,速率常数为0.031 min-1;经过4次循环实验后,RhB降解率从98.8%降低至98.4%,表现出良好的稳定性和可重复利用性。光催化剂BiOCl/PANI实现了电子和空穴对的快速分离,降低了二者在催化剂内部的复合速率,提高了光催化性能。
【大学化学】doi: 10.3866/PKU.DXHX202401056
铬族元素的Cr2、Mo2、W2基团具有相对稳定性,科学家对此做了实验验证和理论计算,试图找出原因。本文梳理了相关研究脉络及最新进展,从“它们的成键方式如何?”以及“可以怎样被进一步稳定?”两个问题出发,对铬族元素中的双原子基团六重键作用进行了分析、归纳和讨论。作者认为,Cr2、Mo2、W2基团的不稳定性来源于两原子间密集电子的斥力;因此,各种稳定该基团的方法本质上都是从减小电子密度、解决电子斥力入手。
【大学化学】doi: 10.12461/PKU.DXHX202405147
仪器分析实验“分子荧光法测定罗丹明B的含量”存在实验过于简单、未考虑实际情况等问题。因此,本改进实验在三维荧光扫描模式下获取样本数据,不进行复杂预处理,而是运用化学计量学算法解析出目标分析物的纯信号,进而实现了染色辣椒中罗丹明6G和123的同时测定。本改进实验提高了学生全面考虑问题和创新解决问题的能力。
【无机化学学报】doi: 10.11862/CJIC.20240183
利用碳空位缺陷有序化策略构筑了多层六方孔洞MXene电极材料,在软包超级电容器中实现了高比容量和高能量密度水系钾离子存储。该电极材料具有较大比表面积的三维六方孔洞结构,为储钾提供了更多的活性位点。结合六方孔洞内壁新暴露的钛原子的化合价变化引起的赝电容效应,阐明了多层六方孔洞MXene水系钾离子超级电容器比容量提高的内在原因。通过密度泛函理论计算多层六方孔洞MXene对钾离子的吸附能,并结合电化学储钾性能实验及动力学分析,确定了钾离子被吸附的最佳位置,得出了钾离子的吸附规律。通过定量分析多层六方孔洞MXene中电子的能带结构和差分电荷密度等电子传输规律,揭示了其水系钾离子超级电容器具有高电导率和良好倍率性能的内在机理。
【无机化学学报】doi: 10.11862/CJIC.20240219
A simple two-step hydrothermal method synthesized four different CdS/Fe3O4 photocatalysts with varying ratios of mass of CdS to Fe3O4. The composition and morphology of the prepared samples were investigated using X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Solid UV reflectance spectra testing found that CdS/Fe3O4 nanocomposites had good light absorption throughout the spectral range, promoting their photocatalytic properties. Under visible light irradiation, CdS/Fe3O4 (2:5) with a mass ratio of 2:5 exhibited excellent photocatalytic performance, with a degradation rate of 98.8% for rhodamine B. Furthermore, after five cycles of photocatalytic degradation reaction, the rhodamine B degradation rate remained at 96.2%, indicating that the photocatalysts have good photocatalytic stability.
【无机化学学报】doi: 10.11862/CJIC.20250028
A flower-like BiOBr photocatalyst (CS/BiOBr) was prepared by using the carbon material derived from corn straw (CS) as the carrier. The prepared composites were characterized by X - ray diffraction (XRD), Fourier transform infrared (FIIR) spectra, scanning electron microscope (SEM), X - ray photoelectron spectra (XPS), and UV-Vis diffuse reflectance spectra (UV-Vis DRS). The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr, which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr. The bandgap of the composite was narrower compared with the pure BiOBr. The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation, and a higher first-order reaction rate constant (k) of 0.043 7 min-1 than BiOBr (0.014 6 min-1), and exhibited excellent stability and reusability during the cyclic run. The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes. Superoxide radicals and holes were the major active species.
【无机化学学报】doi: 10.11862/CJIC.20240271
为了探究配体对铈氧簇的形成、结构和性质的影响及铈氧簇的潜在应用,使用糠酸(HFA)作为配体,通过溶液法合成了首例由糠酸根稳定的六核铈氧簇,并利用单晶X射线衍射、粉末X射线衍射、X射线光电子能谱、元素分析、热重和光谱等技术表征了其晶体NH4[Ce6O4(OH)4(FA)12(NO3)(H2O)]·5CH3CN·12H2O (1)的结构、组分和光谱性质。结果发现Ce(Ⅳ)离子即使在酸性条件下也具有较强的水解能力,其自身的水解缩合反应及与HFA的配位反应共同促使了化合物1的形成。通过芬顿反应产生羟基自由基(·OH)并采用甲基紫作为指示剂,进一步研究了化合物1清除自由基的能力。结果表明,其能有效地清除·OH,且清除效率随化合物1溶液体积的增加而提升。
【物理化学学报】doi: 10.3866/PKU.WHXB202402006
有机-无机卤化物钙钛矿太阳能电池(PSCs)因其优异的光伏性能(PCE)和简单的制备工艺而受到广泛关注。然而,界面处的电荷复合是制约PSCs光电转换效率进一步提高的关键因素。本文基于旋涂镀膜法利用室温合成的六氯锡酸铵(AH)晶体对钙钛矿薄膜(PSK)和电子传输层之间的界面进行修饰。AH是一种无机锡基钙钛矿材料,可以钝化PSK中的缺陷,建立更好的晶格匹配,从而提高PSK的质量和结晶度。开尔文探针力显微镜结果证实,AH促进了光生电子的定向迁移。飞秒瞬态吸收光谱结果说明AH有效缩短了电子抽取寿命,促进了界面电子转移。基于AH改性的优点,AH修饰的PSCs具有更高的PCE和更小的迟滞效应。
【无机化学学报】doi: 10.11862/CJIC.20250131
To extend a new family of aminophosphine-coordinated [FeFe]-hydrogenase mimics for catalytic hydrogen (H2) evolution, we carried out the ligand substitutions of diiron hexacarbonyl precursors [Fe2(μ-X2pdt)(CO)6] (X2pdt=(SCH2)2CX2, X=Me, H) with aminodiphosphines (Ph2PCH2)2NY(Y=(CH2)2OH, (CH2)3OH) to obtain two new diiron aminophosphine complexes [Fe2(L1)(μ-Me2pdt)(CO)5] (1) and [Fe2(L2)(μ-H2pdt)(CO)5] (2), where L1=3-[(diphenylphosphaneyl)methyl]oxazolidine, L2=3-[(diphenylphosphaneyl)methyl]-1, 3-oxazinane. Moreover, the structures of 1 and 2 have been fully confirmed by elemental analysis, spectroscopic techniques, and single-crystal X-ray diffraction. Using cyclic voltammetry (CV), we investigated the electrochemical redox performance and proton reduction activities of 1 and 2 in acetic acid (HOAc). The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H2 generation in the presence of HOAc.