Tuning the electrocatalytic hydrogen evolution reaction promoted by [Mo2O2S2]-based molybdenum cycles in aqueous medium

Abstract

We report the syntheses and characterizations, in the solid state and in solution, of three new cyclic polyoxothiomolybdates self-assembled around 2,5-dimethylterephthalate (DMT) and 2,5-bis(trifluoromethyl)terephthalate (DFMT) ligands, namely [Mo12DMT](2-), [Mo12DFMT](2-) and [Mo16DFMT](2-). A series of these two Mo12-compounds completed by the two Mo12-compounds obtained with 2,3,5,6-tetramethylterephthalate and trimesate ligands offer the opportunity to compare their electro-catalytic properties for reduction of protons into hydrogen. The ability of these compounds to promote the reduction of protons into hydrogen in aqueous medium is evidenced and the influence of the embedded ligand is highlighted, thus allowing proposal of a mechanism for the hydrogen evolution reaction catalyzed by these clusters.

Building an appropriate active-site motif into a hydrogen-evolution catalyst with thiomolybdate [Mo3S13]2− clusters

“…Molecular complexes have also been studied as an intriguing class of HER catalysts, including biomimetic nickel and cobalt complexes [19][20][21][22] and polyoxometalates. 23,24 Many molecular electrocatalysts, however, have been found to be stable only in nonaqueous solvents or require very large overpotentials to achieve appreciable turnover frequencies. 25 Herein, we report on the development of a new and interesting molecular HER catalyst, thiomolybdate [Mo3S13] 2nanoclusters that, upon supporting onto carbon electrode surfaces, bridges molecular and solid state electrocatalysis.…”

Electrocatalytic properties of {Mo3S4}-based complexes with regard to the hydrogen evolution reaction and application to PEM water electrolysis

“…45 More generally, molecular molybdenum sulphide species have been extensively studied and considered as versatile chemical platform allowing to develop multifunctional catalytic materials, such as metalsubstituted derivatives or coordination complexes, specifically designed with regard to the applied process. [46][47][48][49][50][51][52] In order to further investigate the HER properties of such class of compounds, we report herein on the development of {Mo 3 S 4 }-based molecular HER catalysts, taking benefit of the well-known chemical properties of the aqua cluster [Mo 3 S 4 (H 2 O) 9 ] 4+ , used as precursor in this work. 53 As illustrated in Fig.…”

Chemical Diversity of Metal Sulfide Minerals and Its Implications for Prebiotic Catalysis

“…Mo sulfide possesses a laminated lattice structure that is highly amenable to electric and structural modifications, and its catalytic property has therefore been investigated in different crystal phases, including hexagonal MoS2 (2H-MoS2), chemically exfoliated metallic MoS2 (1T MoS2), amorphous MoSx, Mo-S clusters (Mo3S4 -), and Mo-Cu binary-metal sulfide (Cu2MoS4) [111][112][113][114][115][116]), and with various degrees of non-stoichiometric defects [113,115], doping [123,124], and hybridization [125][126][127]. From the results of spectroscopic analyses, including in situ and ex situ X-ray absorption [128], XPS [129], EPR [130] and Raman spectroscopy [111,130] [116,[133][134][135].…”