Research Article
Naujokaitis A, Zalneraviciu
Abstract
MoS2 Nanoplatelet Arrays as a Support for Decoration with Pt Nanoparticles and its Effect on Electrochemical Water Splitting Developing an active electro catalyst for water splitting remains one of the key tasks for further progress of this technology. In this study, the surprising enhancement of HER performance was obtained at Ti substrate covered by few-layered nanoplatelet molybdenum sulphides/oxides mixture array fabricated via hydrothermal synthesis and subsequent electrochemical decoration with ultra-small Pt nanoparticles. By this way, the enhancement of HER efficiency up to 10 times and more was observed, achieving the performance of HER characteristic to Pt surface. To disclose the transformations carried out during prolonged and intensive hydrogen evolution at the constructed electrodes, scanning electron microscopy (SEM) and high resolution SEM (HRSEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and cyclic voltammetry investigations were performed. The results obtained were attributed to the creation of numerous extremely active catalytic sites along the nanoplatelet edges and on their surface throughout the desulfurization by a stream of evolved hydrogen and deposition of Pt/PtO nanoparticles. Surprising ultra-high catalytic efficiency of HER with an overpotential of few mV and current density exceeding 190 mA cm-2 at -200 mV vs RHE bias voltage was obtained using just 6.0 mg m-2 Pt loading.