Photoresponse Enhancement in MAPbI₃/Si Heterojunction Through P(VDF-TrFE) Doping and Introducing Pyro-Phototronic Effect

The photovoltaic effect and pyro-phototronic effect offer a promising approach to enhance self-powered photodetectors (PDs) performance. However, further investigation is warranted to explore the performance improvement, the impact of pyroelectric effect, and the underlying coupling mechanism. In this study, heterojunction PDs consisting of ITO/CH3NH3(MA)PbI3:P(VDF-TrFE)/Si are prepared, with P(VDF-TrFE) concentration varying from 0 to 1 wt.%. The results reveal that the concentration of P(VDF-TrFE) has a significant impact on the photovoltaic response, with the optimal concentration being 0.8 wt.%. The PD displays a broadband response (405-1064 nm) at zero bias, peaking at 780 nm. Furthermore, the introduction of P(VDF-TrFE) significantly enhances the responsivity (R) and detectivity (D), resulting in a remarkable increase of 5814%. The values of R and D reach 1.93 x 10(4) V W-1 and 1.99 x 10(12) Jones, respectively. Moreover, the PD demonstrates an ultrafast response time of 81.6/208 mu s. Additionally, the pyro-phototronic effect extends the response wavelength to 1550 nm, surpassing the spectral limit of the heterojunction. Importantly, the heterojunction exhibits improved weak light detection ability. At 6.37 mu W cm(-2) intensity, R and D show an impressive increase of 21 683%, reaching 8.99 x 10(4) V W-1 and 9.3 x 10(13) Jones, respectively.