Huang Hongpu, Liu Kai, Yang Fulin, Cai Junlin, Wang Shupeng, Chen Weizhen, Wang Qiuxiang, Fu Luhong, Xie Zhaoxiong, Xie Shuifen
Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing, College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China.
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, China.
Angew Chem Int Ed Engl. 2023 Dec 21;62(52):e202315752. doi: 10.1002/anie.202315752. Epub 2023 Nov 23.
Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi-step catalytic reactions. Here, we report a defect-derived strategy for creating surface phosphorous vacancies (P-vacancies) on nanometric Rh P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P-terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of H and OH on perfect P-terminated Rh P{200} facets (p-Rh P) can be bypassed on defective Rh P{200} surfaces (d-Rh P). The P-vacancies enable the exposure of sub-surface Rh atoms to act as exclusive H adsorption sites. Therein, the H cooperates with the OH on the peripheral P-sites to effectively accelerate the alkaline HOR. Defective Rh P nanowires (d-Rh P NWs) and perfect Rh P nanocubes (p-Rh P NCs) are then elaborately synthesized to experimentally represent the d-Rh P and p-Rh P catalytic surfaces. As expected, the P-vacancy-enriched d-Rh P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p-Rh P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts.
打破催化剂表面的原子均匀性对于构建协同活性中心以应对复杂的多步催化反应具有重要意义。在此，我们报道了一种缺陷衍生策略，用于在纳米级RhP电催化剂上创建表面磷空位（P空位），以大幅提升碱性氢氧化反应（HOR）的电催化性能。该策略打破了热力学稳定的P端接表面的均匀性和原子规则性。密度泛函理论计算初步证实，在有缺陷的RhP{200}表面（d-RhP）上可以绕过H和OH在完美P端接的RhP{200}晶面（p-RhP）上的竞争吸附行为。P空位使次表面Rh原子暴露出来，作为唯一的H吸附位点。其中，H与周边P位点上的OH协同作用，有效加速碱性HOR。然后精心合成了有缺陷的RhP纳米线（d-RhP NWs）和完美的RhP纳米立方体（p-RhP NCs），以实验方式代表d-RhP和p-RhP催化表面。正如预期的那样，富含P空位的d-RhP NWs催化剂在碱性HOR电催化中表现出极高的催化活性和出色 的CO耐受性，质量活性分别达到p-RhP NCs和商业Pt/C的5.7倍和14.3倍。这项工作为开发高效多相催化剂打破表面原子均匀性提供了思路。
