【大学化学】doi: 10.12461/PKU.DXHX202311079
制备无毒的ZnGa2O4:Bi3+荧光材料,其同时具备可调多色荧光、动态光致变色及热致变色的三模式发光性质。我们利用这种类似“变色龙”的荧光特性设计了三种信息安全实施方案,实验互动性强且具有趣味性,有良好的科普实践展示效果,有助于激发学生对化学学科的学习热情,进而帮助青少年体会“美丽化学”的丰富内涵。
【大学化学】doi: 10.12461/PKU.DXHX202504044
本文进行了具有气致变色特性的蒽环基超分子聚合物材料在创新型化学实验中的初探。利用该材料所制备的“变色龙”图案在固态时呈现橙红色荧光,在特定蒸气作用下迅速响应变为黄色或绿色荧光。实验设计涵盖超分子聚合物材料制备、荧光表征以及蒸气响应测试,将超分子化学中的分子识别与刺激响应原理融入实践教学。学生可通过直观的荧光变色现象观察,结合光谱数据解析,深入理解智能材料的结构-性能关系。本研究将学科前沿与基础实验相结合,有效强化学生的综合实验技能和创新能力。
【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。
【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.
【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.
