Controllable fabrication and structure evolution of hierarchical 1T-MoS2 nanospheres for efficient hydrogen evolution

Abstract

The layered materials have demonstrated great prospects as cost-effective substitutes for precious electrocatalysts in hydrogen evolution reaction. Research efforts have been devoted to synthesizing highly conductive MoS2 with the substantial cardinal plane and edge active sites. Here, we successfully synthesized a hierarchical 1T/2H–MoS2 with sodium ion insertion via a facile hydrothermal method. The contents of the 1T-phase can be flexibly controlled by different hydrothermal temperatures (160 ∼ 200 °C). And the modified uniformly dispersed 1T/2H–MoS2 nanospheres with different d spacings were designed to enhance the electrocatalytic efficiency by adding SiO2 and through the ion exchange process of NaOH and HF solution. The as-synthesized Na+ intercalated 1T-MoS2 nanosphere with an expanded interlayer of 0.95 nm obtained at 160 °C exhibits a prominent electrocatalytic performance of hydrogen evolution reaction with a comparable overpotential of 255 mV and a remarkably small Tafel slope of 44 mV/decade. Therefore, this study provides a facile and controllable strategy to yield interlayer-expanded 1T-MoS2 nanospheres, making it a potentially competitive hydrogen evolution catalyst for the hydrogen cell.

Keywords

• MoS2
• Phase evolution
• Ion intercalation
• Hydrogen evolution reaction