Effect Of Charged Particle Radiation On Microstructure And Electrochemical Performance Of Ti₃C₂T_x Film

Ti₃C₂T_x MXenes,as a new family of two-dimensional materials,has promising applications in space tribology and energy storage due to its unique layered microstructure,huge specific surface area,high conductivity,and excellent mechanical property.However,its space application is unavoidably challenged by the charged-particle radiation.Thus,the design,modification,and radiation protection for the Ti₃C₂T_x based materials are based on the deep understanding of the radiation damage on its microstructure,of which is rarely reported.In this investigation,a self-resembled Ti₃C₂T_x flexible film was prepared using vacuum filtration method.The150 ke V charged particle radiation tests were conducted on the Ti₃C₂T_x films.The microstructure of the charged particle irradiated Ti₃C₂T_x films were characterized by means of X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and transmission electron spectroscopy（TEM）.The electrochemical performance of the irradiated Ti₃C₂T_x film was also measured.The test results show that,the charged particle radiation leads to Ti-C bonds breaking,and partial removal of-F groups.With increasing charged particle fluence,the F content is decreased.The proton radiation with 1×1015 cm-2 fluence has distinct annealing effect on Ti₃C₂T_x films,which enhances its crystalline degree and increases the valence number of Ti element,facilitating the improvement of electrochemical property.At the same time,the wettability of Ti₃C₂T_x film in H2SO4 aqueous solution is increased under 1E15 cm-2 proton radiation.The electrochemical measurement results show that the electrochemical properties of Ti₃C₂T_x nanosheets are decreased after proton irradiation under fluences of 5×1014cm-2,5×1015 cm-2 and 1×1016 cm-2.When proton fluence reaches 1×1015 cm-2,the specific capacitance of Ti₃C₂T_x film is significantly increased and the electrochemical performance is improved.The specific capacitance of the electron irradiated Ti₃C₂T_x film shows a decrease trend,and the electrochemical performance decreases.The following factors that charged particle irradiation facilitates the enhancement of electrochemical performance of Ti₃C₂T_x film,i.e.increased crystalline degree and valence number of Ti element,and decreased contact angle and surface termination groups.