Fluorinated\nTransition Metal Carbides for Flexible\nSupercapacitors

Abstract

The\nmixed, hexagonal, layered carbides and nitrides known as the\nMAX phases are utilized in diverse electrochemical devices, in similar\nways as graphite is used. Fluorinated graphite shows significantly\nimproved electrochemical energy storage performance when compared\nto graphite, and while the carbides MAX phases are extensively studied,\nfluorine-doped MAX phases are yet to be examined. Herein, a series\nof fluorinated MAX phase materials suitable as a viable electrode\nmaterial for flexible supercapacitors (FSCs) were prepared by using\na fluorination route. The insertion of fluorine as a heteroatom into\nthe MAX phase structures leads to a significant improvement of their\nstructural, wettability, and electrochemical properties. Various electrochemical\nand morphological characterizations were performed to investigate\nthe influence of various metal (M) elements (e.g., Ti, Ta, V, Cr,\nand Mo) on the fluorinated MAX phase electrodes. Moreover, the electrochemical\noutcomes demonstrate that the fluorinated materials effectively increase\nthe capacitance and power density of the electrodes, and the fundamental\nconcepts are established. As a proof concept, supremely FSCs were\nutilized as a portable power source for powering a digital timer.