Multifunctional 2D materials have been exploited for highly intricate applications in engineering and medicine, including energy, bioimaging and drug delivery. In this study, an MXene material, Ti₃C₂T_x, was developed to play dual functional roles in wastewater treatment and electrochemical energy storage. First, Ti₃C₂T_x MXene demonstrated its high capacity for the adsorption of selected cationic dyes such as Rhodamine B in aqueous solutions. Meanwhile, both XPS and Raman spectroscopy indicated that Ti₃C₂T_x hosted the organic dyes in its interlayer voids through intercalation. After the in situ carbonization, conversion of the organic dyes to carbon led to the formation of novel carbon-filled Ti₃C₂T_x (Ti₃C₂T_x/C) for electrochemical applications. With the increased interlayer thickness of carbon within Ti₃C₂T_x/C, the carbon-filled Ti₃C₂T_x hetero-structure was eventually applied as a supercapacitor electrode; it displayed a high specific capacity of 226 F g⁻¹ at 1 A g⁻¹. Our unique approach of cationic dye adsorption/carbonization significantly enhanced the transport paths of electrolyte ions into the MXene, i.e. it exhibited high performance and cycling stability, with 94% retention over 8000 cycles. Our study paves the way to achieve scalable and environmental friendly processes for the development of high-performance 2D nanomaterials for energy storage.

中文翻译：

---

双功能Ti3C2Tx MXene用于废水处理和电化学储能

多功能2D材料已被广泛用于工程和医学领域，包括能量，生物成像和药物输送。在这项研究中，开发了一种MXene材料Ti ₃ C ₂ T _x，以在废水处理和电化学能量存储中发挥双重功能。首先，Ti ₃ C ₂ T _x MXene表现出了其在水溶液中吸附选定的阳离子染料（如若丹明B）的高容量。同时，XPS和拉曼光谱均表明Ti ₃ C ₂ T _x通过插层在其层间空隙中占据有机染料。后在原位碳化，有机染料向碳的转化导致形成用于电化学应用的新型碳填充Ti ₃ C ₂ T _x（Ti ₃ C ₂ T _x / C）。随着Ti ₃ C ₂ T _x / C内碳层厚度的增加，最终将填充碳的Ti ₃ C ₂ T _x异质结构用作超级电容器电极。它在1 A g ^-1下显示出226 F g ^-1的高比电容。我们独特的阳离子染料吸附/碳化方法极大地增强了电解质离子向MXene的传输路径，即它表现出高性能和循环稳定性，在8000个循环中保留了94％。我们的研究为实现可扩展和环保的工艺铺平了道路，以开发用于储能的高性能2D纳米材料。