Fabrication of bifacial sandwiched heterojunction photoconductor – Type and MAI passivated photodiode – Type perovskite photodetectors

In this work, we report novel heterojunctions perovskite photodetector architecture utilizing metal-free contact electrodes. The metal-free contact electrodes were exploited to fabricate photoconductor – type perovskite photodetector. The attempt to investigate the effect of passivating the active layers of the as – proposed architecture with electrolytic MAI gave rise to a photodiode – type perovskite photodetector. These two photodetector types are sensitive and responsive to light sources through their dual transparent electrodes faces (N-face and T-face). We also showed that passivating the surfaces of the sandwiched perovskite layers with MAI solution improves the performance of the fabricated photodetectors, where the detectivity is enhanced by a factor of hundred compared to non-passivated devices. The proposed photodetectors architectures demonstrate champion dual-detectivity (1.77 × 10¹⁴ Jones for N-face and 4.64 × 10¹⁴ Jones for T-face), dual-responsivity (1.94 × 10³ A/W for N-face and 1.61 × 10³ A/W for T-face) and high dual – sensitivity (3.3 × 10² for N-face and 1.1 × 10² for T-face). All these properties were obtained from the two faces of the MAI passivated photodetectors under 0.02 mW/cm² red LED illumination and at −2.0 bias voltage. This novel architecture may scale up towards building energy and cost efficient classes of optoelectronic and photovoltaic devices which are responsive to light in two directions.