▎ 摘　　要

We report Ag-nanowires (Ag NWs)-doped graphene/p-type SiO2-embedded Si quantum dots (p-SQDs: SiO2)/n-Si heterojunction photodetectors (PDs). It is found that the p-n junctions show excellent PD characteristics including photocurrent/dark current (on/off) ratio of 10(5) at 0 V bias, meaning "self-powered". The PDs optimized at an Ag NWs concentration of 0.1wt % exhibit 0.32-0.65 AW(-1) responsivity (R), similar to 85% external quantum efficiency (EQE), and similar to 4.5 similar to 10(12) cm Hz(1/2)/W detectivity in the visible range of 500-900 nm. The linear dynamic range and response time of the PDs at 532 nm are similar to 83 dB and similar to 2 mu s, respectively. The loss of the R is only 15% of its initial value while the PDs are kept for 700 h in air. In particular, the EQE of the self-powered PD is comparable to that of commercially-available Si PD and better than those of previously-reported graphene/Si PDs. These results suggest that the doped graphene/p-SQDs: SiO2/n-Si heterojunctions are promising for their applications in self-powered optoelectronic devices. (C) 2018 Elsevier B.V. All rights reserved.