Development of high-performance and cost-effective catalysts for electrocatalytic hydrogen evolution reaction (HER) play crucial role in the growing hydrogen economy. Recently, the atomically dispersed metal catalysts have attracted increasing attention due to their ultimate atom utilization and great potential for highly cost-effective and high-efficiency HER electrocatalyst. Herein, we propose a high-temperature treatment strategy to furtherly improve the HER performance of atomically dispersed Pt-based catalyst. Interestingly, after appropriate high-temperature treatment on the atomically dispersed Pt_0.8@CN, the Pt species on the designed N-doped porous carbon substrate with rich defect sites can be re-dispersed to single atom state with new coordination environment. The obtained Pt_0.8@CN-1000 shows superior HER performance with overpotential of 13 mV at 10 mA cm⁻² and mass activity of 11,284 mA/mg_Pt at −0.1 V, much higher than that of the pristine Pt_0.8@CN and commercial Pt/C catalyst. The experimental and theoretical investigations indicate that the high-temperature treatment induces the restructuring of coordination environment and then the optimized Pt electronic state leads to the enhanced HER performances. This work affords new strategy and insights to develop the atomically dispersed high-efficiency catalysts.

用于电催化制氢反应（HER）的高性能，高性价比催化剂的开发在不断发展的制氢经济中起着至关重要的作用。近来，原子分散的金属催化剂由于其最终的原子利用和具有高成本效益和高效率的HER电催化剂的巨大潜力而​​引起了越来越多的关注。在此，我们提出了一种高温处理策略，以进一步提高原子分散的Pt基催化剂的HER性能。有趣的是，在对原子分散的Pt _0.8 @CN进行适当的高温处理之后，可以在新的配位环境下将设计好的具有丰富缺陷位点的N掺杂多孔碳衬底上的Pt物种重新分散为单原子态。获得的Pt _0.8@ CN-1000表现出卓越的HER性能，在10 mA cm ^-2时的过电势为13 mV，在-0.1 V时的质量活性为11,284 mA / mg _Pt，远高于原始Pt _0.8 @CN和市售Pt / C催化剂。实验和理论研究表明，高温处理诱导了配位环境的重构，然后优化的Pt电子态导致了HER性能的增强。这项工作为开发原子分散的高效催化剂提供了新的战略和见识。