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Optoelectronic properties of metal halide perovskites were modulated using Sn-doping. Photoconductors were fabricated based on the Sn-doped perovskite films, and the devices were optimized to present weak temperature-dependent performance metrics.

Hybrid perovskites have recently attracted attention in both materials science and opto-electronics research, because of their excellent opto-electronic properties and facile fabrication. Perovskite-based photovoltaic devices, photodetectors, and light-emitting diodes have exhibited unprecedented success. Moreover, optically pumped perovskite lasers have been reported with various crystal shapes. However, most of these lasers are fabricated from solution-grown micro/nano crystals, and thus lack reproducibility. Here, we present controllable fabrication of formamidinium lead iodide (FAPbI3) perovskite microdisks by thermal co-evaporation, coupled with femtosecond laser direct writing. After careful investigation of dimensional effects, including the impact of diameter and thickness, we achieved an ultra-low threshold of ∼3 μJ cm−2. Furthermore, we investigated the relationship of lasing performance with carrier dynamics by transient absorption. We found that a longer carrier lifetime can reduce the pump threshold. These microdisk lasers based on femtosecond laser fabrication of evaporated perovskite thin films show exceptional reproducibility, rendering them extremely suitable for mass production; hence, they offer a promising method for low-cost, on-chip coherent light sources.

Chalcogenides have attracted great attention in the past few decades because of their excellent processability and outstanding optoelectronic properties. Particularly, AgBiS2 has been the frontier of the photovoltaic field in the past few years. AgBiS2 possesses fascinating merits, such as a high absorption coefficient, suitable bandgap, decent charge transport properties and superior material stability. However, most of the efficient AgBiS2-based devices are fabricated with AgBiS2 quantum dots, which require long fabrication time and complicated synthetic steps. Moreover, most of the reports focused on photovoltaic devices, and AgBiS2-based photodetectors have not been reported yet. Based on the challenges listed above, we developed AgBiS2 photodetectors based on a molecular precursor method with a p–i–n device structure. These photodetectors exhibited broadband spectral response with decent detectivity and fast response time of 700 ns. In addition, these devices also demonstrated outstanding air, light and water stability.

Photodetectors based on organic–inorganic hybrid perovskites have emerged as prominent opto-electronic devices for next generation imaging and photodetection. Most of the thin film based devices suffer from poor device stability and large device capacitance. On the other hand, photodetectors based on single crystals have been reported as an alternative approach. However, single crystals are limited by the processing. In this work, we introduce a top down method to fabricate crushed perovskite crystal/polymer composite films. The prepared films possess synergestic advantages of single crystals and polymers, such as, enhanced material stability, maintenance of excellent charge transport and feasibility to prepare thick films. Prototypical thick junction photodiodes based on such composite films are fabricated. The devices presented decent photoresponse in the visible region, low dark current and noise, improved stability and compelling fast response of 800 ns. Benefiting from both large crystal size and composition engineering, the thick junction devices exhibited superior device stability with negligible degradation after 50 days’ storage and testing.