Atomic‐Level Pt Electrocatalyst Synthesized via Iced Photochemical Method for Hydrogen Evolution Reaction with High Efficiency

Abstract

In heterogeneous catalysis, metal particle morphology and size can influence markedly the activity. It is of great significance to rationally design and control the synthesis of Pt at the atomic level to demonstrate the structure‐activity relationship toward electrocatalysis. Herein, a powerful strategy is reported to synthesize graphene‐supported platinum‐based electrocatalyst, that is, nanocatalysts with controllable size can be prepared by iced photochemical method, including single atoms (Pt‐SA@HG), nanoclusters (Pt‐Clu@HG), and nanocrystalline (Pt‐Nc@HG). The Pt‐SA@HG exhibits unexpected electrocatalytic hydrogen evolution reaction (HER) performances with 13 mV overpotential at 10 mA cm−2 current densities which surpass Pt‐Clu@HG and Pt‐Nc@HG. The in situ X‐ray absorption fine structure spectroscopy (XAFS) and density functional theory (DFT) calculations determine the Pt‐C3 active site is linchpin to the excellent HER performance of Pt‐SA@HG. Compared with the traditional Pt‐Nx coordination structure, the pure carbon coordinated Pt‐C3 site is more favorable for HER. This work opens up a new way to adjust the metal particle size and catalytic performance of graphene at a multiscale level.

Regulating the electronic structure of single-atom catalysts for electrochemical energy conversion

“…Low-temperature chemical reduction is an accessible method for fabricating SACs in a low-temperature environment. 41,42 The precursors containing metal cations frozen in ice are reduced by ultraviolet irradiation or reducing agents (such as NaBH 4 ). 100 The size of the metal catalysts can be controlled by adjusting the growth and nucleation process.…”

“…101 The Pt SACs were fabricated by irradiating the frozen low-concentration Pt precursor solution with a xenon lamp. 42 Therefore, it was necessary to lower the reaction temperature and the concentration of the precursor solution to fabricate SACs.…”

“…[25][26][27][28][29] Since SACs were rst reported in 2011, numerous precious metal SACs, such as Pt, Ir, Ru, and Au, have been obtained through different synthetic strategies, i.e., co-precipitation, impregnation, atomic layer deposition, high-temperature pyrolysis, and low-temperature chemical reduction. [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] To further lower the cost of precious metal SACs, 3d transition metal SACs, such as Fe, Co, and Ni, were also fabricated via bonding with O, N, S, and P atoms or anchoring at the defects to increase the durability. [50][51][52] Metal SAs anchored to the substrates interact with each other to generate many active sites.…”

Hierarchical Electrodes of MoS 2 Nanoflakes Wrapped on CNTs in Wood-Derived Porous Carbon Frameworks for a High-Performance Hydrogen Evolution Reaction

“…4 Pt-based precious metals are the most widely studied catalysts for HER, but their high cost and scarcity severely hinder their widespread applications. 5,6 Accordingly, a great effort is needed to explore the economically efficient, earth-rich, and highly active HER catalysts.…”

“…However, the hydrogen evolution reaction (HER) on the cathode of water electrolysis generally has slow kinetics, and high-performance catalysts are required to hasten the reaction . Pt-based precious metals are the most widely studied catalysts for HER, but their high cost and scarcity severely hinder their widespread applications. , Accordingly, a great effort is needed to explore the economically efficient, earth-rich, and highly active HER catalysts.…”