Hydrothermally synthesized α-MnS nanostructures for electrochemical water oxidation and photocatalytic hydrogen production

Abstract

Manganese based nanostructures have been extensively used in different applications such as solar cell, photoelectrochemical and opto-electronics devices. Manganese sulfide nanostructure was prepared employing hydrothermal technique with different concentration of hydrazine hydrate (HZH). In observed XRD pattern, high intensity peak at (200) confirmed cubic structure formation of MnS nanostructures. MnS nanomaterials with high concentration of reducing agent such as hydrazine hydrate exhibited better morphology with maximum conductivity and investigated by using TEM images. MnS@4 ml HZH achieved large 191F/g specific capacitance at 10 mV/s in 1 M KOH. MnS@4 ml HZH sample obviously showed high 191F/g specific capacitance than other two samples. MnS@4 ml HZH exhibited high current density (295 mA/g) with the low overpotential of 184 mV. Strong reducing and complexing agent of hydrazine hydrate controlled nanoparticles size and structure is beneficial to improve its surface area and porous nature of synthesized material resulting to exhibit the excellent OER and HER activity. The obtained surface area, pore volume and pore diameter were found to be 13.95 m2/g, 0.027 cc/g and 3.948 nm respectively. The photocatalytic hydrogen production was also studied for MnS@4 ml HZH sample under light irradiation of 450-watt Xe-Hg lamp, which exhibited the average rate activity of 223.4 mmol.h−1.