Alloying Pt into Ni partially amorphous for promoted alkaline hydrogen production

作者：Zeng, Liming^*; Yuan, Tianxiang; Liu, Zerui; Zhu, Yongyang; Wu, Daifeng; Wang, Dongxing; Zhou, Qing; Tang, Renheng

来源：Journal of Colloid and Interface Science, 2023, 634: 897-905.

DOI：10.1016/j.jcis.2022.12.066

• Partially amorphous
• Pt-Ni alloy
• Alkaline hydrogen evolution reaction

Aiming at the sluggish water dissociation step in alkaline hydrogen evolution reaction (HER), the platinum-nickel alloy material (PtNi10/C) featuring unique crystalline/amorphous structure supported on carbon black is deliberately designed and fabricated via a reversely rapid co-precipitation and mild thermal reduction strategy. Electrochemical results show that only 66 mV of overpotential is needed for PtNi10/C to drive a current density of 10 mA cm(-2) at a lower platinum loading (8.3 lgPt cm(-2) geo), which is much lower than that of other catalysts with a single metal source(S-Ni/C and S-Pt/C) and even the commercial Pt/C catalyst (20 wt%). The target catalyst also exhibits smaller tafel slope value (16.73 mV dec(-1)) and electrochemical impedance value, enabling a fast kinetics rate for water dissociation. Partial crystallization facilitates moderate adsorption of intermediates, while the high-valence Ni(II) and Pt(II) species serve as pivotal driving force for the kinetic dissociation of water. The unique microstructure of PtNi10/C shows a remarkable advantage toward HER in alkaline but acidic medium. In addition, other transition metal-based catalysts following the similar protocol are also fabricated and present varying degrees of HER performance. Hence, the facile and rapid co-precipitation/thermal reduction strategy proposed in this study provides some guidelines for designing high-efficiency alkaline HER catalysts.

• 单位
  武汉大学