The rapid advancement in the miniaturization, integration, and intelligence of electronic devices has escalated the demand for customizable micro-supercapacitors (MSCs) with high energy density. However, efficient microfabrication of safe and high-energy MXene MSCs for integrating microelectronics remains a significant challenge due to the low voltage window in aqueous electrolytes (typically ≤0.6 V) and limited areal mass loading of MXene microelectrodes. Here, we tackle these challenges by developing a high-concentration (18 mol kg⁻¹) “water-in-LiBr” (WiB) gel electrolyte for MXene symmetric MSCs (M-SMSCs), demonstrating a record high voltage window of 1.8 V. Subsequently, additive-free aqueous MXene ink with excellent rheological behavior is developed for three-dimensional (3D) printing customizable all-MXene microelectrodes on various substrates. Leveraging the synergy of a high-voltage WiB gel electrolyte and 3D-printed microelectrodes, quasi-solid-state M-SMSCs operating stably at 1.8 V are constructed, and achieve an ultrahigh areal energy density of 1772 μWh cm⁻² and excellent low-temperature tolerance, with a long-term operation at −40°C. Finally, by extending the 3D printing protocol, M-SMSCs are integrated with humidity sensors on a single planar substrate, demonstrating their reliability in miniaturized integrated microsystems.

中文翻译：

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三维（3D）打印MXene高压水性微型超级电容器具有超高面能量密度和耐低温能力

电子设备小型化、集成化和智能化的快速发展，提高了对高能量密度可定制微型超级电容器（MSC）的需求。然而，由于水性电解质中的低电压窗口（通常≤0.6 V）和 MXene 微电极的面积质量负载有限，用于集成微电子的安全和高能 MXene MSC 的高效微制造仍然是一个重大挑战。在这里，我们通过开发用于 MXene 对称 MSC (M-SMSC) 的高浓度 (18 mol kg ⁻¹ )“LiBr 水​​”(WiB) 凝胶电解质来应对这些挑战，展示了创纪录的 1.8 V 高电压窗口随后，开发了具有优异流变行为的无添加剂水性 MXene 墨水，用于在各种基材上三维 (3D) 打印可定制的全 MXene 微电极。利用高压WiB凝胶电解质和3D打印微电极的协同作用，构建了在1.8 V下稳定工作的准固态M-SMSC，并实现了1772 μWh cm ^-2的超高面能量密度和优异的低能量密度。耐温能力强，可在-40℃下长期工作。最后，通过扩展 3D 打印协议，M-SMSC 与湿度传感器集成在单个平面基板上，证明了它们在小型化集成微系统中的可靠性。