Multifunctional Self-Combustion Additives Strategy to Fabricate Highly Responsive Hybrid Perovskite Photodetectors

Abstract

To resolve the inherent trade-off issue between responsivity and detectivity in FA0.9Cs0.1PbI3 perovskite photodetectors, this paper proposes a novel strategy using multifunctional self-combustion additives (urea and ammonium nitrate). During the early stages of crystallization, urea allows for the formation of a strong Lewis complex-derived low-dimensional intermediate phase; this suppresses the formation of perovskite nuclei, while ammonium ions assist the preferred grain growth along the [110] direction. During the high-temperature annealing steps, a self-combusting exothermic reaction occurs between urea as a fuel and NH4NO3 as an oxidizer, through which a locally supplied heat facilitates the removal of residual urea and byproducts. These multifunctional roles of self-combustible additives facilitate the production of high-quality, enlarged grain-structured perovskite films with improved optoelectronic properties, as confirmed by various analyses, including impedance spectroscopy and intensity-modulated photocurrent spectroscopy. The resulting FA0.9Cs0.1PbI3-based photodiode-type photodetectors exhibit outstanding performance, such as a high responsivity (0.762 A W–1) and specific detectivity (over 5.08 × 1013 Jones) at a very low external reverse bias (−0.5 V). Our findings clearly suggest that the multifunctional self-combustion additives strategy could help realize the full potential of FA1–x Cs x PbI3 as a photodiode-type photodetector.

Photoelectrochemical Application and Charge Transport Dynamics of a Water-Stable Organic–Inorganic Halide (C6H4NH2CuCl2I) Film in Aqueous Solution

“…The transport time τ t and interfacial charge recombination lifetime τ e are directly and inversely proportional to charge collection. Meanwhile, the interfacial charge collection efficiency η c of a photoelectrochemical cell is typically calculated using the following formula , …”

Defect Passivation via Additive Engineering to Improve Photodetection Performance in CsPbI2Br Perovskite Photodetectors

“…On the one hand, the introduction of a small amount of the PEG additive can increase the nucleation energy barrier and reduce the quantity of the perovskite crystal nucleus . On the other hand, such interaction would suppress the conversion of Pb 2+ ions to CsPbI 2 Br perovskite crystals and slow down the crystallization process. , Therefore, the average grain size of CsPbI 2 Br was increased with increasing PEG concentration from 0 to 0.4 mg mL –1 . However, further increasing the PEG concentration to 0.8 mg mL –1 reduced the grain size due to the disruption of perovskite crystallization by the excess PEG additive.…”

Stable Formamidinium‐Based Centimeter Long Two‐Dimensional Lead Halide Perovskite Single‐Crystal for Long‐Life Optoelectronic Applications

“…Besides, the obtained responsivity of (BA) 2 FAPb 2 I 7 compound is compared with reported photodetectors fabricated using other 2D and 3D hybrid perovskites (Table S1, Supporting Information). [43][44][45][46][47][48][49][50] There are few reports on the enhanced responsivity of 2D hybrid perovskites using different strategies. Tan et al used graphene as a protection layer and top contact for effective carrier collection in their (BA) 2 PbBr 4 photodetector to enhance the stability and responsivity.…”

“…Besides, the obtained responsivity of (BA) 2 FAPb 2 I 7 compound is compared with reported photodetectors fabricated using other 2D and 3D hybrid perovskites (Table S1, Supporting Information). [ 43–50 ] There are few reports on the enhanced responsivity of 2D hybrid perovskites using different strategies. Tan et al.…”