Abstract
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.
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•Sandwiched architecture heterojunction bifacial perovskite photodetectors was designed for direct illumination.•Effects of passivating the layers of sandwiched perovskite layer with MAI solution was investigated.•The photodetectors were electrically, optically and electrochemically characterized as bifacial devices.•Excellent performance with detectivity and responsivity ~5.96 × 1013 Jones & 1110 A/W was achieved.•Quantum efficiency of 3000% was recorded for the MAI passivated photodetector at 450 nm.