Diiron azadithiolate clusters supported on carbon nanotubes for efficient electrocatalytic proton reduction

Herein, we report the synthesis of a new diiron azadithiolate compound {(μ-SCH 2 ) 2 N(C 6 H 4 CH 2 CH 2 OH-4)}Fe 2 (CO) 6 ( 1 ) and especially its covalent attachment onto benzoxy-functionalized single-walled carbon nanotubes ( f -SWCNTs ) to construct the first example of diiron azadithiolate clusters supported on carbon nanotubes ( 1- f -SWCNTs ) for efficient electrocatalytic proton reduction to H 2 in an aqueous medium. The structure and morphology of the as-prepared hybrid 1- f -SWCNTs have been well characterized by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Notably, the 1- f -SWCNT hybrid absorbed on the cheap glassy carbon electrode exhibits a much more positive reduction potential ( E pc ) in pure water relative to an organic solvent (MeCN) and an outstanding turnover frequency (TOF) of 9444 s −1 for H 2 production in the presence of 0.2 N aqueous H 2 SO 4 as a proton source under electrochemical conditions. The first example of diiron azadithiolate clusters supported on carbon nanotubes ( 1- f -SWCNTs ) was constructed via covalent attachment. This nanohybrid shows efficient electrocatalytic proton reduction with a TOF of 9444 s −1 in 0.2 N aqueous H 2 SO 4 .