High-entropy alloys (HEAs) are promising candidates for the electrocatalyst of hydrogen evolution reaction (HER) due to their unique properties such as cocktail electronic effect and lattice distortion effect. Herein,...High-entropy alloys (HEAs) are promising candidates for the electrocatalyst of hydrogen evolution reaction (HER) due to their unique properties such as cocktail electronic effect and lattice distortion effect. Herein, the ultrasmall (sub-2 nm) nanoparticles of PtRuCoNiCu HEA with uniform element distribution are highly dispersed on hierarchical N-doped carbon nanocages (hNCNC) via low-temperature thermal reduction, denoted as us-HEA/hNCNC. The optimal us-HEA/hNCNC exhibits excellent HER performance in 0.5 M H_(2)SO4 solution, achieving an ultralow overpotential of 19 mV at 10 mA·cm^(−2) (without iR-compensation), high mass activity of 13.1 A·mgnoble metals ^(−1) at −0.10 V and superb stability with a slight overpotential increase of 3 mV after 20,000 cycles of cyclic voltammetry scans, much superior to the commercial Pt/C (20 wt.%). The combined experimental and theoretical studies reveal that the Pt&Ru serve as the main active sites for HER and the CoNiCu species modify the electron density of active sites to facilitate the H* adsorption and achieve an optimum M-H binding energy. The hierarchical pore structure and N-doping of hNCNC support also play a crucial role in the enhancement of HER activity and stability. This study demonstrates an effective strategy to greatly improve the HER performance of noble metals by developing the HEAs on the unique hNCNC support.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFA1500900)the National Natural Science Foundation of China(No.52071174)+1 种基金the Natural Science Foundation of Jiangsu Province(Major Project:No.BK20212005)the Foundation of Science and Technology of Suzhou(No.SYC2022102).
文摘High-entropy alloys (HEAs) are promising candidates for the electrocatalyst of hydrogen evolution reaction (HER) due to their unique properties such as cocktail electronic effect and lattice distortion effect. Herein, the ultrasmall (sub-2 nm) nanoparticles of PtRuCoNiCu HEA with uniform element distribution are highly dispersed on hierarchical N-doped carbon nanocages (hNCNC) via low-temperature thermal reduction, denoted as us-HEA/hNCNC. The optimal us-HEA/hNCNC exhibits excellent HER performance in 0.5 M H_(2)SO4 solution, achieving an ultralow overpotential of 19 mV at 10 mA·cm^(−2) (without iR-compensation), high mass activity of 13.1 A·mgnoble metals ^(−1) at −0.10 V and superb stability with a slight overpotential increase of 3 mV after 20,000 cycles of cyclic voltammetry scans, much superior to the commercial Pt/C (20 wt.%). The combined experimental and theoretical studies reveal that the Pt&Ru serve as the main active sites for HER and the CoNiCu species modify the electron density of active sites to facilitate the H* adsorption and achieve an optimum M-H binding energy. The hierarchical pore structure and N-doping of hNCNC support also play a crucial role in the enhancement of HER activity and stability. This study demonstrates an effective strategy to greatly improve the HER performance of noble metals by developing the HEAs on the unique hNCNC support.