Chen Yihan, Chen Jinwei, Zhang Jie, Xue Yali, Wang Gang, Wang Ruilin
College of Materials Science and Engineering, Sichuan University, Chengdu 610065, Sichuan Province, PR China.
Engineering Research Center of Alternative Energy Materials & Devices, Ministry of Education, Sichuan University, Chengdu 610065, Sichuan Province, PR China.
Inorg Chem. 2022 Mar 28;61(12):5148-5156. doi: 10.1021/acs.inorgchem.2c00329. Epub 2022 Mar 15.
Pt electrocatalysts with high activity and durability have still crucial issues for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). In this study, a novel catalyst consisting of Pt nanoparticles (NPs) on TiO/C composites (TiO-V-H/C) with abundant oxygen vacancies (V) is proposed, which is abbreviated as PTO-V-H/C. The introduction of V helps anchor highly dispersed Pt NPs with low loading and strengthen the strong metal-support interaction (SMSI), which benefits to the enhanced ORR catalytic activity. Moreover, the accelerated durability test (ADT) demonstrates the higher retention of ORR activity for PTO-V-H/C. Experimental and theoretical analyses reveal that electronic interactions between Pt NPs and TiO/C composite support give rise to an electron-rich Pt NPs and strong SMSI effect, which is favorable for the electron transfer and stabilization of Pt NPs. More importantly, the assembled PEMFC with PTO-V-H/C shows only 6.9% of decay on maximum power density after 3000 ADT cycles while the performance of Pt/C sharply decreased. This work provides a new insight into the unique vacancy regulation of dispersive Pt on metal oxides for superior ORR performance.
具有高活性和耐久性的铂基电催化剂在质子交换膜燃料电池（PEMFC）的氧还原反应（ORR）中仍存在关键问题。在本研究中，提出了一种新型催化剂，即在具有丰富氧空位（V）的TiO/C复合材料（TiO-V-H/C）上负载铂纳米颗粒（NPs），简称为PTO-V-H/C。V的引入有助于锚定低负载量的高度分散的铂纳米颗粒，并增强强金属-载体相互作用（SMSI），这有利于提高ORR催化活性。此外，加速耐久性测试（ADT）表明PTO-V-H/C的ORR活性保留率更高。实验和理论分析表明，铂纳米颗粒与TiO/C复合载体之间的电子相互作用产生了富电子的铂纳米颗粒和强SMSI效应，这有利于铂纳米颗粒的电子转移和稳定性。更重要的是，采用PTO-V-H/C组装的PEMFC在3000次ADT循环后最大功率密度仅衰减6.9%，而Pt/C的性能则急剧下降。这项工作为通过独特的空位调控在金属氧化物上分散铂以实现优异的ORR性能提供了新的见解。
