Hydrogen evolution reaction catalyzed by platinum nanoislands decorated on three-dimensional nanocarbon hybrid

Abstract

Platinum-based catalysts are ineluctable and superior among the various other HER-efficient electrocatalysts. Enhancing the electrocatalytic activity by reducing the amount of Pt is highly challenging. In this work, a systematic physicochemical and electrochemical study on platinum nano-islands (Pt NIs) architectured on three-dimensional nanocarbon hybrid (3D-NCHy) was carried out. A detailed comparison of the catalyst activity with respect to Pt decorated on other carbon nanostructures has been evaluated. Pt NIs@3D-NCHy demonstrated substantially high degree of stability and durability during the electrochemical evaluations. The electrochemical hydrogen evolution reaction (HER) studies were carried out using linear sweep voltammetry (LSV), Tafel polarization, and electrochemical impedance spectroscopy (EIS). Pt NIs@3D-NCHy catalyst exhibited lowest overpotential value of −13 mV for attaining a current density of −10 mAcm−2. The stability and durability of the catalyst was tested by continuous accelerated degradation test (ADT) for 10,000 cycles, and a high degree of stability was observed for the material. The turnover frequency (TOF) was estimated to be 6.3 s−1 at an overpotential (ɳ) = −70 mV. Interesting, the as-synthesized hybrid with a Pt loading of 3.8 μgcm−2, established performance equivalence to that of 20 wt.% Pt/C which has Pt loading of 20 μgcm−2.