Rational Design of Polymeric Electrocatalysts with Atomically Dispersed Platinum for Efficient and Durable Hydrogen Evolution

ABSTRACT Designing high‐performance platinum (Pt) single‐atom electrocatalysts for acidic hydrogen evolution reaction (HER) is of significance yet remains challenging. An elaborated design of support materials is crucial to address the key issues posed by the low concentration of hydrogen intermediates ( * H) and their weak adsorption on the Pt single atoms in high‐valence states. Herein, a cation‐π interaction engineering strategy was proposed to immobilize Pt single atoms onto N‑heterocyclic conjugated polymers, generating moderate cation‐π interactions that stabilize Pt single atoms in low‐valence states with favorably‐elevated Pt 5d‐band centers for enhanced * H adsorption on them. Furthermore, this design can create a favorable local chemical environment with a high * H coverage near Pt single atoms owing to the sufficient * H supply rate, stemming from the facilitated water dissociation on the N atoms of N‑heterocyclic conjugated polymers. The resulting catalyst with a low Pt loading (1.41 wt.%) achieves a low overpotential of 14 mV at 10 mA cm −2 and an outstanding stability for 1500 h of continuous operation at 100 mA cm −2 toward acidic HER catalysis. This cation‐π interaction engineering strategy offers a promising approach for electrocatalytic performance optimization of polymeric electrocatalysts that can be further extended to widespread energy‐conversion systems beyond HER.