Co/Mn/Mo掺杂加速NiSe2重构以提高其电催化尿素氧化性能
雷明杰, 胡文婷, 林可心, 孙秀娟, 张澔珅, 钱烨, 康彤玥, 吴秀琳, 廖海龙, 潘园, 张玉微, 魏笛野, 高平
【物理化学学报】doi: 10.1016/j.actphy.2025.100083
尿素氧化反应(UOR)是一种很有前途的可再生能源生产技术,为电解水制氢提供了有效的替代方案,因此开发高效稳定的UOR催化剂至关重要。本文通过NaBH4还原和硒化策略合成了富含Co、Mn和Mo的硒化镍催化剂(NiCoMnMo-Se),该催化剂具有球形纳米颗粒与纳米片共存结构。X射线光电子能谱(XPS)、紫外-可见分光光度法(UV-vis)和原位bode相图表明,Mn和Mo的协同效应调节了Ni/Co的电子结构,提高了硒化物的电导率并加速加速电荷转移动力学,从而促进Ni2+/Co2+快速转变为活性Ni3+/Co3+,并显著降低了NiCoMnMo-Se的起始电位。在UOR过程中,大部分Mo和Se被氧化成钼酸盐和硒酸盐溶解在电解质中,暴露出更多的Ni(Co)OOH活性位点,从而加快UOR反应。另外,Mn的引入稳固了活性位点,极大地增强催化剂的整体稳定性。正如预期的那样,NiCoMnMo-Se催化剂在UOR过程中表现出优异的电催化和稳定性性能,在仅1.38 V vs. RHE (相对于可逆氢电极)的电位下实现了50 mA·cm−2的电流密度,并在50 mA·cm−2电流密度下运行50 h后电压仅上升3.0%。当NiCoMnMo-Se和商业Pt/C组装成用于碱性尿素电解的双电极体系时,它只需要1.59 V vs. RHE便达到50 mA·cm−2。
关键词: 尿素氧化反应, 制氢, NiCoMnMo-Se, 协同效应, 尿素电解, 镍基硒化物
Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
Haifeng ZHENG, Xingzhe GUO, Yunwei WEI, Xinfang WANG, Huimin QI, Yuting YAN, Jie ZHANG, Bingwen LI
【无机化学学报】doi: 10.11862/CJIC.20250029
The poor electrical conductivity of metal-organic frameworks (MOFs) limits their electrocatalytic performance in the oxygen evolution reaction (OER). In this study, a Py@Co-MOF composite material based on pyrene (Py) molecules and {[Co2(BINDI)(DMA)2]·DMA}n (Co-MOF, H4BINDI=N,N′-bis(5-isophthalic acid)naphthalenediimide, DMA=N,N-dimethylacetamide) was synthesized via a one-pot method, leveraging π-π interactions between pyrene and Co-MOF to modulate electrical conductivity. Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes, achieving an overpotential of 246 mV at a current density of 10 mA·cm-2 along with excellent stability. Density functional theory (DFT) calculations reveal that the formation of O* in the second step is the rate-determining step (RDS) during the OER process on Co-MOF, with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH* intermediate for Co sites.
关键词: pyrene, metal-organic frameworks, composite catalyst, oxygen evolution reaction, density functional theory
Crystallinity and oxidation degree tuning of Ru for alkaline hydrogen oxidation
Yuanjun LIU, Jiayang JIANG, Rui WANG, Jiangnan HU, Chaoyi YUAN, Xingmei GUO, Junhao ZHANG, Guoxing ZHU
【无机化学学报】doi: 10.11862/CJIC.20250373
Developing high-performance electrocatalysts for the alkaline hydrogen oxidation reaction (HOR) is essential for advancing alkaline hydrogen fuel cells. Here, we report the synthesis of ruthenium (Ru) catalysts with tuned crystallinity and oxidation degree. By combining template-assisted synthesis with controlled thermal treatment, amorphous, partially crystalline, highly crystalline, and partially oxidized Ru products were successfully obtained. Catalysts with moderate crystallinity and partial oxidation exhibit enhanced catalytic activity toward the alkaline hydrogen oxidation reaction. The optimized Ru-RuO2 catalyst achieved a mass activity of 81.66 mA·mgRu-1, which was 2.27 times that of commercial Pt/C under identical conditions. The improved activity is attributed to the synergistic effect of moderate crystallinity and partial oxidation, which favors a favorable Tafel-Volmer reaction pathway.
关键词: hydrogen oxidation, Ru catalyst, crystallinity, fuel cells, catalytic activity

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