Han Weiwei, Cai Xinuo, Liao Jiahong, He Yi, Yu Chunlin, Zhang Xingwang
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang Province 310058, China.
Institute of Zhejiang University-Quzhou, Quzhou, Zhejiang Province 324000, China.
ACS Appl Mater Interfaces. 2024 Sep 11;16(36):47610-47619. doi: 10.1021/acsami.4c09431. Epub 2024 Aug 30.
The development of proton exchange membrane water electrolysis is a promising technology for hydrogen production, which has always been restricted by the slow kinetics of the oxygen evolution reaction (OER). Although IrO is one of the benchmark acidic OER electrocatalysts, there are still challenges in designing highly active and stable Ir-based electrocatalysts for commercial application. Herein, a Ru-doped IrO electrocatalyst with abundant twin boundaries (TB-RuIrO@ITO) is reported, employing indium tin oxide with high conductivity as the support material. Combing the TB-RuIrO nanoparticles with ITO support could expose more active sites and accelerate the electron transfer. The TB-RuIrO@ITO exhibits a low overpotential of 203 mV to achieve 10 mA cm and a high mass activity of 854.45 A g at 1.53 V vs RHE toward acidic OER, which exceeds most reported Ir-based OER catalysts. Moreover, improved long-term stability could be obtained, maintaining the reaction for over 110 h at 10 mA cm with negligible deactivation. DFT calculations further reveal the activity enhancement mechanism, demonstrating the synergistic effects of Ru doping and strains on the optimization of the d-band center (ε) position and the adsorption free energy of oxygen intermediates. This work provides ideas to realize the trade-off between high catalytic activity and good stability for acidic OER electrocatalysts.
质子交换膜水电解技术的发展是一种很有前景的制氢技术，但其一直受到析氧反应（OER）缓慢动力学的限制。尽管IrO是基准酸性OER电催化剂之一，但在设计用于商业应用的高活性和稳定的Ir基电催化剂方面仍存在挑战。在此，报道了一种具有丰富孪晶界的Ru掺杂IrO电催化剂（TB-RuIrO@ITO），采用高导电性的氧化铟锡作为载体材料。将TB-RuIrO纳米颗粒与ITO载体相结合可以暴露出更多的活性位点并加速电子转移。相对于可逆氢电极（RHE），TB-RuIrO@ITO在酸性OER中实现10 mA cm时的过电位低至203 mV，在1.53 V时的质量活性高达854.45 A g，超过了大多数已报道的Ir基OER催化剂。此外，还可获得改善的长期稳定性，在10 mA cm下保持反应超过110 h且失活可忽略不计。密度泛函理论（DFT）计算进一步揭示了活性增强机制，证明了Ru掺杂和应变对d带中心（ε）位置和氧中间体吸附自由能优化的协同作用。这项工作为实现酸性OER电催化剂高催化活性和良好稳定性之间的权衡提供了思路。
