Zhou Lingxi, Shao Yangfan, Yin Fang, Li Jia, Kang Feiyu, Lv Ruitao
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
Institute of Materials Research and Shenzhen Geim Graphene Center, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
Nat Commun. 2023 Nov 23;14(1):7644. doi: 10.1038/s41467-023-43466-x.
Stabilizing active sites of non-iridium-based oxygen evolution reaction (OER) electrocatalysts is crucial, but remains a big challenge for hydrogen production by acidic water splitting. Here, we report that non-stoichiometric Ti oxides (TiO) can safeguard the Ru sites through structural-confinement and charge-redistribution, thereby extending the catalyst lifetime in acid by 10 orders of magnitude longer compared to that of the stoichiometric one (Ru/TiO). By exploiting the redox interaction-engaged strategy, the in situ growth of TiO on Ti foam and the loading of Ru nanoparticles are realized in one step. The as-synthesized binder-free Ru/TiO catalyst exhibits low OER overpotentials of 174 and 265 mV at 10 and 500 mA cm, respectively. Experimental characterizations and theoretical calculations confirm that TiO stabilizes the Ru active center, enabling operation at 10 mA cm for over 37 days. This work opens an avenue of using non-stoichiometric compounds as stable and active materials for energy technologies.
稳定非铱基析氧反应（OER）电催化剂的活性位点至关重要，但对于酸性水分解制氢来说仍是一项巨大挑战。在此，我们报道非化学计量比的钛氧化物（TiO）可通过结构限制和电荷重新分布来保护Ru位点，从而使催化剂在酸性环境中的寿命比化学计量比的催化剂（Ru/TiO）延长10个数量级。通过采用氧化还原相互作用参与策略，一步实现了TiO在泡沫钛上的原位生长以及Ru纳米颗粒的负载。所制备的无粘结剂Ru/TiO催化剂在10和500 mA cm时的OER过电位分别为174和265 mV。实验表征和理论计算证实，TiO稳定了Ru活性中心，使其能够在10 mA cm下运行超过37天。这项工作开辟了一条使用非化学计量比化合物作为能源技术中稳定且活性材料的途径。
