This research reports a continuous output ionic thermoelectric (i‐TE) system based on MXene/PVA (polyvinyl alcohol) hydrogel, by utilizing thermo‐diffusion of Cu2+ and Cl− ions and the redox reaction involving Cu/Cu2+ at the electrode interfaces. The thermopower of the i‐TE system can be independently tuned to a value of −3.13 mVK−1 by adjusting the ion diffusivity via MXene (Ti3C2Tx). The i‐TE system demonstrates a rapid response time of less than 100 s, outperforming any other polyelectrolyte‐based system. Crucially, the i‐TE system achieves continuous current output when equipped with copper electrodes, facilitated by the redox reaction involving Cu/Cu2+, and maintains stable long‐term outputs across a range of resistances from 1 kΩ to 1 MΩ. A three‐serial‐connected i‐TE module demonstrates an output voltage of 26 mV with 6 °C temperature difference, confirming the feasibility of creating an array of i‐TE devices for substantial energy output. Beyond energy harvesting, the MXene/PVA hydrogel serves as multifunctional strain/temperature sensors, capable of detecting mechanical strains via the piezoresistive effect and locating finger contact points via the ionic thermoelectric effect.

中文翻译：

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作为连续离子热电发生器和应变/温度传感器的多功能 MXene/PVA 水凝胶


本研究报道了一种基于 MXene/PVA（聚乙烯醇）水凝胶的连续输出离子热电 （i-TE） 系统，该系统利用 Cu2+ 和 Cl− 离子的热扩散以及电极界面处涉及 Cu/Cu2+ 的氧化还原反应。i-TE 系统的热功率可以通过 MXene （Ti3C2Tx） 调节离子扩散率，独立调整到 −3.13 mVK−1 的值。i-TE 系统表现出小于 100 秒的快速响应时间，优于任何其他基于聚电解质的系统。至关重要的是，i-TE 系统在配备铜电极时可实现连续电流输出，这得益于涉及 Cu/Cu2+ 的氧化还原反应，并在 1 kΩ 至 1 MΩ 的电阻范围内保持稳定的长期输出。一个三串联的 i-TE 模块的输出电压为 26 mV，温差为 6 °C，证实了创建一系列 i-TE 器件以实现大量能量输出的可行性。除了能量收集之外，MXene/PVA 水凝胶还可用作多功能应变/温度传感器，能够通过压阻效应检测机械应变，并通过离子热电效应定位手指接触点。