析氢反应和析氧反应是电化学水分解和金属–空气电池等可再生能源技术的基础反应。各种过渡金属(Co、Fe、Ni等)基催化剂由于具有良好的电催化活性而被大量探索,以作为贵金属潜在的替代品。本研究成功制备出负载于氮掺杂石墨烯(NGO)上的双功能电催化剂(Co5.47N/NGO)。在1 M KOH中,达到10 mA/cm2的电流密度,OER过电位需352 mV,HER过电位需104 mV。(Co5.47N/NGO)作为电解池的阴极和阳极时,1.79 V的电压就能达到10 mA/cm2的电流密度,并表现出优异的稳定性。该研究简化了氮化钴的合成过程,并且片状NGO减少了纳米粒子的团聚,提供了大量的活性位点,从而提高了电催化活性。The hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are fundamental reactions in renewable energy technologies such as electrochemical water splitting and metal-air batteries. A variety of transition metal (Co, Fe, Ni, etc.)—based catalysts have been extensively explored due to their good electrocatalytic activity as potential substitutes for noble metals. In this study, a bifunctional electrocatalyst (Co5.47N/NGO) supported on nitrogen-doped graphene (NGO) was successfully prepared. In 1 M KOH, to reach a current density of 10 mA/cm², the overpotential for OER is 352 mV and the overpotential for HER is 104 mV. When (Co5.47N/NGO) serves as the cathode and anode of the electrolytic cell, a voltage of 1.79 V can achieve a current density of 10 mA/cm2 and exhibit excellent stability. This research simplifies the synthesis process of cobalt nitride, and the flake-shaped NGO reduces the agglomeration of nanoparticles and provides a large number of active sites, thus improving the electrocatalytic activity.
金属–载体相互作用在调控金属纳米颗粒的电子结构及其稳定金属纳米颗粒方面发挥着关键作用。本研究以具有独特空腔结构的葫芦[6]脲(CB6)为前驱体,通过水热合成结合高温热解的策略,成功制备了氮掺杂碳负载钌纳米颗粒催化剂(Ru/CN)。系统研究了合成过程中前驱体不同处理工艺及不同煅烧温度对材料结构和电催化析氢性能的影响。电化学测试结果表明,所制备的Ru/CN催化剂在碱性电解液中表现出优异的析氢反应性能,达到10 mA cm–2电流密度时仅需12 mV的过电位,且在10 mA cm–2恒定电流密度下连续电解220小时后仍保持优异的催化稳定性,展现出显著的性能优势。这一发现为设计高效稳定的HER电催化剂提供了新的思路和实验依据。Metal-support interaction is vital of modulating electronic structure of metal nanoparticles as well as stabilizing these nanoparticles. In this study, nitrogen-doped carbon-loaded ruthenium nanoparticle catalysts (Ru/CN) were successfully prepared by hydrothermal synthesis combined with high-temperature pyrolysis strategy using cucurbit [6] uril (CB6), which has a unique cavity structure, as a precursor. The effects of different treatment processes of precursors and different calcination temperatures on the structure and electrocatalytic hydrogen reaction performance of the materials during the synthesis were systematically investigated. The electrochemical test results showed that the prepared Ru/CN catalyst exhibited excellent hydrogen reaction performance in alkaline electrolyte, requiring only 12 mV overpotential to reach 10 mA cm−2 current density, and maintained excellent catalytic stability after 220 h of continuous electrolysis at a constant current density of 10 mA cm−2, demonstrating significant performance advantages. This finding provides a new idea and experimental basis for the design of efficient and stable HER electrocatalysts.
金属–载体相互作用不仅调控金属的电子结构,还可以稳定金属纳米颗粒,被认为是一种提高电解水析氢反应性能的有效策略。本文采用4,4’-联吡啶与Cs2[closo-B12H12]为前驱体,通过静电组装制备了新型硼有机聚合物(BOPs),并以此作为还原剂和载体,原位还原–煅烧两步法制备硼氮双掺杂碳载体负载钌纳米颗粒催化剂(Ru/BCN)。主要探究了合成过程中不同煅烧温度对于Ru/BCN的HER性能的影响,研究发现Ru/BCN-700展现出最佳的析氢活性,在碱性介质中仅需要17 mV的过电位就可达到10 mA cm−2的电流密度,并且具有良好的稳定性和耐久性。
