Spontaneous amorphous oxide-interfaced ultrafine noble metal nanoclusters for unexpected anodic electrocatalysis

• Published in: Chem catalysis Vol. 1; no. 5; pp. 1104 - 1117
• Main Authors: Liu, Shangheng, Ji, Yujin, Yang, Shize, Li, Leigang, Shao, Qi, Hu, Zhiwei, Pao, Chih-Wen, Chen, Jeng-Lung, Chan, Ting-Shan, Zhu, Ting, Li, Youyong, Huang, Xiaoqing, Lu, Jianmei
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 21.10.2021
• Subjects: anodic electrocatalysis; nanocluster; noble metal; oxide interface; spontaneous; oxide interface; nanocluster; spontaneous; SDG7: Affordable and clean energy; anodic electrocatalysis; noble metal
• ISSN: 2667-1093; 2667-1093
• DOI: 10.1016/j.checat.2021.08.016

Noble metals are considered a key branch of electrocatalysts. Unfortunately, their contributions to anodic reactions still face a big challenge. Here, guided by density functional theory, significant breakthroughs have been achieved by constructing a unique spontaneously oxidized interface in noble metal sub-nanocluster (SNC) catalysts depending on strong surface affinity. The spontaneous oxide interfaces with the amorphous covering on the rhodium (Rh) SNCs (diameter <2 nm). Turnover frequency of the Rh/RhOx catalyst reached 2.19 s−1 for the oxygen evolution reaction (OER) in alkaline media, 72.0-times and 3.3-times higher than those of Rh and Rh2O3, respectively. Moreover, the high activity can be maintained for at least 20 h at 50 mA cm−2. Such a unique strategy provides a general platform to largely facilitate the OER performances of platinum, palladium, and iridium catalysts, opening up a new and promising avenue for the design of noble metal catalysts for expansive applications. [Display omitted] •A class of Rh SNCs with clean surface is successfully synthesized•The Rh SNCs realize spontaneous oxidation interface at room temperature•Spontaneous oxidation interface effect improves the OER performance of Rh SNCs•Spontaneous oxidation strategy can be extended to other noble metals (Pt, Pd, and Ir) Noble metals have been regarded as the most essential material for various catalytic fields. However, in the anode reaction, especially the oxygen evolution reaction (OER), the catalyst usually needs high temperature to completely oxidize. Such treatment reduces the native conductivity or leads to sintering, weakening the catalytic activity and stability. Therefore, research still lacks a versatile guideline to upgrade noble metal catalysts as universal catalysts for practical applications. Here, we report a theoretical calculation-guided strategy that develops spontaneous oxide interfaced metal sub-nanoclusters as the unprecedented catalysts for anodic reaction. This strategy greatly improves the OER and hydrazine oxidation reaction performances while being able to adapt to a variety of noble metals, opening up a new and promising avenue for the design of noble metal catalysts for expansive applications. A unique spontaneously oxidized interface was constructed in noble metal sub-nanoclusters (SNCs) due to the strong surface affinity, which changed the rate-limiting step of reaction. The Rh/RhOx SNCs represent a major breakthrough for OER, with the unique interface delivering enhanced intrinsic turnover frequency of 2.19 s−1 for OER in 1 M KOH, 72.0-times higher than that for metallic Rh. More importantly, the strategy provides a general platform to largely facilitate the OER performances of platinum-, palladium-, and iridium-based catalysts.