In the last decade, the combination of two or more semiconductors with different dimensionality to improve the performance of optical devices has become widespread. Graphdiyne, a recently emerged interesting 2D semiconductor with its sp-sp2 structure and elastic band gap, is still being explored by researchers in various fields, especially in optoelectronic devices. The van der Waals heterojunctions of graphdiyne with zero-dimensional photosensitizers such as quantum dots could be a great candidate for novel photodetectors. In this work, we constructed a simple and highly sensitive phototransistor by implementing graphdiyne as the charge carrier layer and graphdiyne quantum dots as the photosensitizer layer. The photoresponsivity of the proposed heterostructure was measured to be 4403.6A/W, which is 4.45 times higher than pristine GDY. Compared to pure GDY with an on/off ratio and mobility of (0.131 ± 0.011) ˟ 103 and (1.77 ± 0.085) ˟ 10− 2 cm2/V s, respectively., the GDY/GQD heterostructure exhibited an on/off ratio and mobility of (1.5 ± 0.03) ˟ 104, (3.3 ± 0.06) ˟ 10− 2 cm2/ Vs, respectively. The proposed heterostructure device responded 2.22 times faster to light irradiation and exhibited 12.5 times faster decay time. The obtained data demonstrate the applicability of our design and its potential for building GDY/GQD heterojunctions based on phototransistors.
