The iteration of intelligent electronic products has promoted the rapid development of flexible transparent electronics, greatly stimulating the demand of matched energy storage units. Flexible transparent zinc-ion hybrid supercapacitors (ZHSCs) not only combine the advantages of high energy density and high power density, but also exhibit excellent transparency, leading a new revolution in flexible electronic technology. Transparent conductive electrode is the most critical component of ZHSCs, which determines the energy storage characteristics of the whole device. Therefore, it is very important to develop advanced electrode materials with high specific capacitance and high optical transmittance. Transition metal carbides/nitrides (MXenes) are considered ideal materials for fabricating ZHSCs due to their high electrical conductivity and large specific surface area. However, it still faces challenges of small flake size and limited electrochemical performance, as well as low synthesis yield, high cost, and difficulty in large-scale application. To address these issues, this work reports a simple and effective method to fabricate high-yield large-sized Ti₃C₂T_x, through in-situ etching approach to prepare multilayer Ti₃C₂T_x (MXene) and mechanical shaking strategy. Using Ti₃C₂T_x electrode as the positive electrode, zinc electro-deposited indium tin oxide/polyethylene terephthalate (ITO/PET) as the negative electrode, and zinc trifluoromethanesulfonate as the electrolyte, an asymmetric ZHSC device was assembled. Experimental results show that when the shaking time is 1.5 h, the Ti₃C₂T_x flake size reaches 5.2 μm with a high yield of 32.4%. The resulting ZHSCs exhibit a voltage window of 1.2 V, a large areal capacitance of 7.79 mF•cm^-2, high power density of 60.0 µW•cm^-2, high energy density of 1.56 µWh•cm^-2, and high transparency of 62.1%. After bending and folding at 180°, the device retains 94.1% of its capacitance. Moreover, the ZHSC-30 device maintains a capacitance retention rate of 82.3% after 1000 cycles at a current density of 600 µA•cm^-2, demonstrating its stable cycling performance. This work provides a powerful method for the fabrication of large-sized MXenes for application in flexible transparent ZHSCs.

Key words: zinc-ion hybrid supercapacitors, flexible transparent electrode, MXene nanosheet, large-size, mechanical shaking