Ti3C2 MXene as Additive for Low‐Cost Textile Supercapacitors with Enhanced Electrical Performance

Abstract Textile‐based energy storage components are paramount for establishing invisible electronic textiles that do not require conventional rigid batteries. A novel and scalable fabrication method is reported for introducing MXene (Ti 3 C 2 T x ) into activated carbon (AC) supercapacitors to enhance electrochemical performance. Supercapacitors are prepared within a single layer of textile with a phase‐inverted polymer membrane fabricated within the textile yarn structure to form a porous, flexible, and mechanically durable separator. MXene is introduced in two different forms: 1) A multilayer MXene (m‐MXene)powder is mechanically mixed with an AC slurry and deposited onto the textile. 2) Delaminated MXene (d‐Mxene) nanosheets are spray‐coated onto the surface of spray coated AC electrode. With an organic electrolyte, 1 M tetraethylammonium tetrafluoroborate in dimethyl sulfoxide, these supercapacitors are electrochemically stable between +/− 2.6 V and demonstrate a maximum areal capacitance of 148.7 mF cm −2 , an energy density of 0.921 mWh cm −2 , and a power density of 1.01 mW cm −2 . The addition of MXenes improves the areal capacitance and by combining both approaches an improvement of 220% is achieved compared with identical supercapacitors with standard AC electrodes. The novelty of this work is to develop a scalable and straightforward solution processing method for introducing MXene into carbon supercapacitor electrodes enabling high‐performance textile‐based energy storage devices.