Gamma irradiated structural modification of Ti3C2Tx for high performance supercapacitors and the hydrogen evolution reaction

Abstract

Gamma irradiation-based synthesis and modification of nanomaterials has emerged as a versatile technique to increase the electrochemically active sites for catalytic reactions. Ionizing radiation has a tremendous effect on the optical, electrical, microstructural, and physicomechanical properties of nanomaterials. By controlling the irradiation parameters such as the absorbed dose rate and the total absorbed dose, tunable synthesis and surface modifications can be achieved. Herein, the gamma irradiation technique was used to modify the Ti₃C₂T_x MXene and the effect on the electrochemical performance of gamma-irradiated Ti₃C₂T_x (γ-Ti₃C₂T_x) for the hydrogen evolution reaction (HER) and supercapacitor applications was studied. The irradiated structure was characterized using X-ray diffraction and scanning electron microscopy, which confirmed the formation of γ-Ti₃C₂T_x MXene. The electrochemical properties were examined by cyclic voltammetry, galvanostatic charge–discharge, and linear sweep voltammetry. The γ-Ti₃C₂T_x exhibits a specific capacitance of 169 F g⁻¹ at 10 A g⁻¹, with 87% capacitance retention after 5000 charge/discharge cycles. Furthermore, the γ-Ti₃C₂T_x-300 electrocatalyst shows an overpotential of 478 mV with a Tafel slope of 157 mV dec⁻¹. The enhanced electrochemical properties of the gamma-irradiated MXene electrodes were attributed to quick diffusion pathways enabled by increased d-spacing upon irradiation.