Maneuvering charge polarization and transport in 2H-MoS2 for enhanced electrocatalytic hydrogen evolution reaction
hydrogen evolution, molybdenum disulfide, charge transport, charge polarization, nanowire
Semiconducting 2H-MoS2 with high chemical stability is a promising alternativeto the existing electrocatalysts for the hydrogen evolution reaction (HER);however, the HER performance largely suffers from the limited number of activeS sites and low mobility for charge transport. In this work, we demonstrate thatthe limitations of 2H-MoS2 for the HER can be overcome by forming hybridstructures with metallic nanowires. Taking the integration with Pd as a proofof-concept, we show with solid experimental evidence that the one-dimensionalstructure of metallic nanowires facilitates electron transport to active S sites,while the interfacial charge polarization between MoS2 and Pd increases theelectron density of the S sites for improved activity. As a result, the hybridstructure exhibits a current density of 122 mA·cm−2 at −300 mV versus RHE anda Tafel slope of 44 mV·decade−1 with excellent durability, well exceeding theperformances of bare 2H-MoS2 and metallic 1T-MoS2. This work provides insightsinto electrocatalyst design based on charge transport and polarization, which canbe extended to other hybrid structures.
Tsinghua University Press
Wei Ye,Chenhao Ren,Daobin Liu,Chengming Wang,Ning Zhang,Wensheng Yan,Li Song,Yujie Xiong, Maneuvering charge polarization and transport in 2H-MoS2 for enhanced electrocatalytic hydrogen evolution reaction. NanoRes.2016, 9(9): 2662–2671