Graphene-MoS₂-Upconversion nanoparticle hybrid photodetector for the visible-NIR spectrum
Digvijay Singh Tomar1*, Sandip Ghosh1, Surojit Chattopadhyay1
1Institute of Biophotonics, National Yang Ming Chiao Tung University, Taipei, Taiwan
* Presenter:Digvijay Singh Tomar,
2D materials like graphene and MoS₂ is considered as a promising material for optoelectronic application due to their outstanding optical activity, and electrical transport properties. Graphene, a 2D material with zero band gap and high electronic mobility, has contributed for faster hybrid photodetectors. MoS₂, on the other hand, resulted in slow photodetectors when conjugated with upconversion nanoparticles (UCNPs) for broadband photodetection. Here, we show, how the introduction of graphene can enhance the speed of the MoS₂–UCNP based photodetectors. We have fabricated MoS₂-UCNPs/Graphene/SiO₂/Si based hybrid photodetector for visible-NIR spectral response. MoS₂-UCNPs/Graphene/SiO₂/Si based hybrid photodetector shows excellent performance with response time of order of 20 ms and responsivity 7.68 A/W at 661 nm and 6.79 A/W at 980 nm illumination under 0.1 V bias voltage. These excellent performances of the photodetector can provide a new direction to enhance the performance of hybrid photodetectors in the future.

Keywords: Graphene, MoS2, Upconversion , Nanoparticles, Photodetector