Pt-O bond as an active site superior to Pt0 in hydrogen evolution reaction
Feiyang Yu, Zhongling Lang, Liying Yin, Kun Feng, Yujian Xia, Huaqiao Tan, Haotian Zhu, Jun Zhong, Zhenhui Kang, Yangguang Li
Abstract
Abstract The oxidized platinum (Pt) can exhibit better electrocatalytic activity than metallic Pt 0 in the hydrogen evolution reaction (HER), which has aroused great interest in exploring the role of oxygen in Pt-based catalysts. Herein, we select two structurally well-defined polyoxometalates Na 5 [H 3 Pt (IV) W 6 O 24 ] (PtW 6 O 24 ) and Na 3 K 5 [Pt (II) 2 (W 5 O 18 ) 2 ] (Pt 2 (W 5 O 18 ) 2 ) as the platinum oxide model to investigate the HER performance. Electrocatalytic experiments show the mass activities of PtW 6 O 24 /C and Pt 2 (W 5 O 18 ) 2 /C are 20.175 A mg −1 and 10.976 A mg −1 at 77 mV, respectively, which are better than that of commercial 20% Pt/C (0.398 A mg −1 ). The in situ synchrotron radiation experiments and DFT calculations suggest that the elongated Pt-O bond acts as the active site during the HER process, which can accelerate the coupling of proton and electron and the rapid release of H 2 . This work complements the knowledge boundary of Pt-based electrocatalytic HER, and suggests another way to update the state-of-the-art electrocatalyst.