Recent advances in two-dimensional graphitic carbon nitride based photodetectors

Graphitic carbon nitride (g-C3N4) is a kind of low cost and environment-friendly 2D polymer semiconductor that exhibits a tunable band gap, high thermal stability, intriguing optoelectronic properties and broad device ap-plications. However, there is hardly any review of g-C3N4 ' s recent development in photodetection devices. Herein, we summarized the recent advances in the 2D g-C3N4 based photodetector. Firstly, the structure and optoelectronic properties of 2D g-C3N4 were introduced. Secondly, recent progress in 2D g-C3N4 based photo-detectors with different device types, such as 2D g-C3N4 based photoconductor, hybrid nanostructure photo-detector, photodiode, perovskite photodetector and piezo-phototronic photodetector were summarized. Finally, some major challenges and opportunities towards the practical optoelectronic device applications of 2D g-C3N4, which need be further investigated, had been discussed. As a pioneer, this review systematically presented the development of 2D g-C3N4 based photodetector in the past years and highlighted their great potential in field of broadband, low-cost, fast-response and high-performance photodetectors. We hope that this review could guide the following development and research of g-C3N4 based photodetectors.