FeS2 bridging function to enhance charge transfer between MoS2 and g–C3N4 for efficient hydrogen evolution reaction

High–performance composite electrocatalysts of g–C 3 N 4 /FeS 2 /MoS 2 for hydrogen evolution reaction (HER) is synthesized by the growth of molybdenum disulfide (MoS 2 ) nanosheets from ferrous disulfide (FeS 2 ) sites supported on graphite–like carbon nitride (g–C 3 N 4 ) substrates. The high conductivity of such composite catalysts is induced by the Fe S bond between FeS 2 and MoS 2 and Fe N bond between FeS 2 and g–C 3 N 4 . These two bonds of Fe S and Fe N can have a bridging function to provide efficient charge transfer channels between g–C 3 N 4 and MoS 2 via chemical bonding rather than physical attachment. Furthermore, the FeS 2 sites can prevent the agglomeration of MoS 2 nanosheets and also seed the MoS 2 to form highly dispersed vertical growth nanosheets with more exposed edging active sites. As a result, this g–C 3 N 4 /FeS 2 /MoS 2 catalyst exhibits both high catalytic HER activity and stability.