Wang Ligang, Su Hui, Tan Guoying, Xin Junjie, Wang Xiaoge, Zhang Zhuang, Li Yaping, Qiu Yi, Li Xiaohui, Li Haisheng, Ju Jing, Duan Xinxuan, Xiao Hai, Chen Wenxing, Liu Qinghua, Sun Xiaoming, Wang Dingsheng, Sun Junliang
College of Chemistry and Molecular Engineering, Peking University, Beijing National Laboratory for Molecular Sciences (BNLMS), 5 Yiheyuan Road, Beijing, 100871, China.
Department of Chemistry, Tsinghua University, Beijing, 100084, China.
Adv Mater. 2024 Apr;36(15):e2302642. doi: 10.1002/adma.202302642. Epub 2024 Jan 20.
The development of facile methods for constructing highly active, cost-effective catalysts that meet ampere-level current density and durability requirements for an oxygen evolution reaction is crucial. Herein, a general topochemical transformation strategy is posited: M-CoS single-atom catalysts (SACs) are directly converted into M-CoOOH-TT (M = W, Mo, Mn, V) pair-sites catalysts under the role of incorporating of atomically dispersed high-valence metals modulators through potential cycling. Furthermore, in situ X-ray absorption fine structure spectroscopy is used to track the dynamic topochemical transformation process at the atomic level. The W-CoS breaks through the low overpotential of 160 mV at 10 mA cm. A series of pair-site catalysts exhibit a large current density of approaching 1760 mA cm at 1.68 V vs reversible hydrogen electrode (RHE) in alkaline water oxidation and achieve a ≈240-fold enhancement in the normalized intrinsic activity compare to that reported CoOOH, and sustainable stability of 1000 h. Moreover, the O─O bond formation is confirmed via a two-site mechanism, supported by in situ synchrotron radiation infrared and density functional theory (DFT) simulations, which breaks the limit of adsorption-energy scaling relationship on conventional single-site.
开发能够满足析氧反应安培级电流密度和耐久性要求的高活性、低成本催化剂的简便方法至关重要。在此，提出了一种通用的拓扑化学转化策略：在通过电位循环引入原子分散的高价金属调节剂的作用下，将M-CoS单原子催化剂（SACs）直接转化为M-CoOOH-TT（M = W、Mo、Mn、V）双位点催化剂。此外，利用原位X射线吸收精细结构光谱在原子水平上追踪动态拓扑化学转化过程。W-CoS在10 mA cm下突破了160 mV的低过电位。一系列双位点催化剂在碱性水氧化中相对于可逆氢电极（RHE）在1.68 V时表现出接近1760 mA cm的大电流密度，与报道的CoOOH相比，归一化本征活性提高了约240倍，并具有1000 h的可持续稳定性。此外，通过原位同步辐射红外和密度泛函理论（DFT）模拟证实了O─O键的形成是通过双位点机制，这打破了传统单位点上吸附能标度关系的限制。
