人類科技日新月異，卻也加劇了對石化燃料的依賴，發展出環境友善的綠色能源勢在必行。碲化亞銅是一種極具展望的熱電材料，但是關於二維碲化亞銅的文獻仍為數不多。在此，我們利用固態化學反應生長碲化亞銅薄膜於石墨烯上，石墨烯作為凡得瓦外延生長的模板以及擴散阻擋層，最終展現出優異的熱電與機電性能。上述材料特性可以達成自發電應力感測器，藉由橫向的溫度差異產生電能，提供快速且耐用的應力感測，有希望成為攜帶式的自主健康檢測器，為生活帶來諸多便利性，展現了二維碲化亞銅與石墨烯異質結構的潛力。

The dependence on fossil fuels has been rapidly increasing with the development of technology. It is imperative to develop eco-friendly green energy, such as thermoelectrics. Particularly, copper(I) telluride is a promising thermoelectric material. However, the synthesis of copper(I) telluride remains in bulk, and copper(I) telluride thin film is still missing. In this work, we use solid-state chemical reaction to grow copper(I) telluride thin films on graphene. Graphene serves as growth template for van der Waals epitaxy of copper(I) telluride and diffusion barrier, and finally exhibit excellent thermoelectric and electromechanical properties. The aforementioned material properties can achieve self-powered strain sensors, which can generate electricity by lateral temperature differences and provide fast and durable stress sensing. It has the potential to become a portable autonomous health monitoring sensors, which not only make our life more convenient but also show the prospect of two-dimensional copper(I) telluride and graphene heterostructures.

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