Researchers have developed hybrid nanostructures by interspersing molybdenum disulphide quantum dots in nanosheets made of the same material1. These hybrid nanostructures could potentially be used as electrocatalysts for producing hydrogen.
To devise a cost-effective technique for producing hydrogen, the researchers fabricated hybrid nanostructures by smearing molybdenum disulphide quantum dots in a few layers of molybdenum disulphide nanosheets using a special technique called liquid phase exfoliation. They then carried out electrochemical experiments that probed the efficiency of these nanostructures in producing hydrogen.
The researchers found that the nanostructures exhibited a low onset potential and a high exchange current density. They attributed this high exchange current density to the improved electron transfer rate resulting from the large combined surface area of the quantum dots and nanosheets. In addition, they found that increasing the number of active edges in the hybrid nanostructures enhances hydrogen production.
The study results revealed that these hybrid materials could be used as high-performance catalysts for splitting water into hydrogen and oxygen, harnessing solar energy. The generated hydrogen could be used as alternative energy carrier in fuel cells. It is feasible to extract these materials in powder form in large quantities to implement industrial applications.
“These hybrid nanostructures will be very useful as high-performance electrocatalysts for producing hydrogen. These materials could also be used in photodetectors, lithium-ion batteries and supercapacitors,” says Manikoth S. Shaijumon, a senior author of the study.
1. Gopalakrishnan, D. et al. MoS2 quantum dot-interspersed exfoliated MoS2 nanosheets. ACS Nano. (2014) doi: 10.1021/nn501479e