Molybdenum Disulfide as a Protection Layer and Catalyst for Gallium Indium Phosphide Solar Water Splitting Photocathodes

Abstract

Gallium indium phosphide (GaInP2) is a semiconductor with promising optical and electronic properties for solar water splitting, but its surface stability is problematic as it undergoes significant chemical and electrochemical corrosion in aqueous electrolytes. Molybdenum disulfide (MoS2) nanomaterials are promising to both protect GaInP2 and to improve catalysis because MoS2 is resistant to corrosion and also possesses high activity for the hydrogen evolution reaction (HER). In this work, we demonstrate that GaInP2 photocathodes coated with thin MoS2 surface protecting layers exhibit excellent activity and stability for solar hydrogen production, with no loss in performance (photocurrent onset potential, fill factor, and light-limited current density) after 60 h of operation. This represents a 500-fold increase in stability compared to bare p-GaInP2 samples tested in identical conditions.

Highly Stable Molybdenum Disulfide Protected Silicon Photocathodes for Photoelectrochemical Water Splitting

“…Increases in photoelectrode performance over the course of stability measurements have previously been observed for other MoS2 protected photocathodes and have been ascribed to the gradual exposure of additional MoS2 edge sites, 15,18 which are known to be the active sites for HER. 22 However, increasing the number of catalytic sites of the MoS2 catalyst should only increase reaction kinetics leading to an increase in the slope of the current-voltage curve and, perhaps its saturation photocurrent value.…”

Strategies for Semiconductor/Electrocatalyst Coupling toward Solar‐Driven Water Splitting

“…It is interesting to note that in this work no additional protective layer was deposited on n + p‐Si, and the MoS 2 layer offers dual functions as both an electrocatalyst and a passivation layer. Similar approach was also employed later on to couple MoS 2 with GaInP 2 /GaAs, which substantially improved the activity and stability of the photocathode.…”

Excellent Microwave Absorption and Electromagnetic Interference Shielding Based on Reduced Graphene Oxide@MoS2/Poly(Vinylidene Fluoride) Composites

“…MoS 2 , as a semiconductor material, has attracted much attention because of its excellent properties for electrochemistry, optoelectrical applications, biosensors, and catalysis . Wang et al.…”

“…[17] MoS 2 ,a sasemiconductor material, has attracted much attention because of its excellent properties for electrochemistry, [18] optoelectrical applications, [19] biosensors, and catalysis. [20] Wang et al investigated the microwave absorption properties of MoS 2 and rGO, and found that the sample, which consisted of 10 wt %M oS 2 /rGO hybrid in paraffin, displayed am icrowave absorption bandwidth of 5.72 GHz at at hickness of 1.9 mm. [21] The maximumR Lr eached À50.9 dB at af requencyo f Reduced graphene oxide (rGO)@MoS 2 composites with al oose structurew ere prepared and added to poly(vinylidene fluoride) (PVDF) to form composites that showed superior microwave absorption and excellent electromagnetic interference shielding performances.…”