This study proposes a Janus structure-based stretchable and breathable thermoelectric skin with radiative cooling (RC) and solar heating (SH) functionalities for sustainable energy harvesting. The challenge of the wearable thermoelectric generator arises from the small temperature difference. Thus, this dual-sided structure maximizes the thermal gradient between the body and the surrounding environment, unlike the previous works that rather concentrate on the efficiency of the thermoelectric generator itself. The Janus structure allows the device to switch to the other mode, optimizing electricity generation from a given weather condition. For these functionalities, for the first time, boron nitride-polydimethylsiloxane (BP) and graphene nanoplatelet-polydimethylsiloxane (GP) nanofiber (NF) are developed as substrates. The BP NF generates the RC capability of ΔT_cooling = 4 °C, and the high solar absorbance of the GP NF enables it to be photothermally heated. The flip-overable thermoelectric skin (FoTES) achieves a maximum power output (P_max) of 5.73 µW cm⁻² in RC mode, surpassing SH mode by 5.55 µW cm⁻² in the morning. In the afternoon, it generates a P_max of 18.59 µW cm⁻² in SH mode, outperforming RC mode by 15.56 µW cm⁻². This work contributes to the advancement of wearable electronics, offering a sustainable power source in a wearable form.

中文翻译：

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采用多模式辐射冷却/太阳能加热辅助大热梯度的高效透气热电皮肤

这项研究提出了一种基于 Janus 结构的可拉伸、透气的热电皮肤，具有辐射冷却 (RC) 和太阳能加热 (SH) 功能，可实现可持续能量收集。可穿戴热电发电机的挑战来自于微小的温差。因此，这种双面结构最大限度地提高了身体与周围环境之间的热梯度，这与之前的工作不同，后者更注重热电发电机本身的效率。Janus 结构允许设备切换到其他模式，优化给定天气条件下的发电。为了实现这些功能，首次开发了氮化硼-聚二甲基硅氧烷（BP）和石墨烯纳米片-聚二甲基硅氧烷（GP）纳米纤维（NF）作为基材。BP NF 产生 Δ T_冷却 = 4 °C 的 RC 能力，并且 GP NF 的高太阳能吸收率使其能够进行光热加热。可翻转热电皮肤（FoTES）在RC模式下实现了5.73 µW cm ^{-2的最大功率输出（} P _max ） ，超过SH模式5.55 µW cm ^-2。下午，它在SH模式下产生18.59 µW cm ^-2的P _max，比RC模式高出15.56 µW cm ^-2。这项工作有助于可穿戴电子产品的进步，以可穿戴形式提供可持续的电源。