A MoSe₂/Si heterojunction photodetector is constructed by depositing MoSe₂ film with vertically standing layered structure on Si substrate. Graphene transparent electrode is utilized to further enhance the separation and transport of photogenerated carriers. The device shows excellent performance in terms of wide response spectrum of UV–visible–NIR, high detectivity of 7.13 × 10¹⁰ Jones, and ultrafast response speed of ≈270 ns, unveiling the great potential for the heterojunction for high-performance optoelectronic devices.

Graphene/Si hole array (SiHA) Schottky junctions show great promise as high-efficiency, cost-effective solar cells. However, their applications are still limited by the severe surface recombination of the nano-hole SiHA and inferior device stability arising from volatile oxidant doping. Here, we demonstrate the construction of high-efficiency graphene/SiHA devices with enhanced device performance and stability. The micro-hole SiHA fabricated by photolithography and reaction ion etching (RIE) possesses a smooth surface, thus ensuring a low surface recombination velocity. Also, the light harvesting of the micro-hole SiHA could be readily tuned by adjusting the hole depth. Introduction of the micro-hole SiHA, along with the use of AuCl₃ for graphene doping, gives rise to a high power conversion efficiency (PCE) of 10.40% for the graphene/SiHA devices. Additionally, the device stability is substantially improved and shows a relatively low degradation ratio after storing in air for 3 months. It is expected that the graphene/SiHA devices will have important applications in new-generation Si solar cells.

We demonstrate the construction of flexible graphene/ultrathin c-Si heterojunction solar cells with excellent flexibility and durability.