Near-UV Phototransistors Based on an All-Inorganic Lead-Free Cs₃Cu₂I₅/CuTCNQ Hierarchical Heterostructure

Abstract

With the rapid advances in metal halide perovskite optoelectronics, eliminating toxic lead from perovskites has been an urgent demand. However, state-of-the-art lead-free perovskite photodetectors are still challenged with issues of low photoresponse, poor stability, etc. Here, all-inorganic lead-free perovskite (Cs 3 Cu 2 I 5 ) single crystals that possess good stability under air exposure are synthesized via a facile solid reaction method. Meanwhile, a higher photoluminescence quantum yield of 95.2% and a prolonged carrier lifetime of 1.127 μs are obtained by further optimizing the synthesis. Benefiting from the polyporous surface and hollow structure of Cu-7,7,8,8-tetracyanoquinodimethane (CuTCNQ) microtubes, more Cs 3 Cu 2 I 5 nanocrystals can adhere on the innershell and outershell of CuTCNQ-15 microtubes. This unique structure contributes to the improved efficiency of utilizing incident light and promotes charge carrier generation and transportation. As a result, the hierarchical CuTCNQ/Cs 3 Cu 2 I 5 (hollow microtube/nanocrystal) heterostructure phototransistor exhibits a high responsivity of 88.36 A W −1 and a large detectivity of 1.66 × 10 12 Jones. The proposed lead-free perovskites and mixed-dimensional heterojunctions are promising for sensitive light detection.

Recent progress of copper halide perovskites: properties, synthesis and applications

“…13(h)), which showed a responsivity as high as 88.36 A W −1 . 93 It is notable that the response range extending from the UV region to the visible region, wherein the energy is smaller than the bandgap. Gu et al further studied this phenomenon and attributed the photoinduced carriers to the photothermoelectric effect (Fig.…”

Recent Advances and Opportunities of Eco‐Friendly Ternary Copper Halides: A New Superstar in Optoelectronic Applications

“…TCH materials have received much attention because of the lowcost, abundance and nontoxicity of copper-related raw material, and wide range of material types, including single crystals (SCs), nanocrystals (NCs), microcrystal, and films, which offer great potential for a variety of optoelectronic applications. [108][109][110][111][112][113][114][115][116][117][118] In this section, we comprehensively summarize and discuss their synthesis methods and growth processes, and the illustration of main synthesis techniques is shown in Figure 4.…”

First-principles calculations for heterostructure studies Involving CsPbI3 perovskite and IV-VI semiconductors

“…Although perovskites have such attractive applications in optoelectronic devices, the toxicity of Pb 2+ will cause environmental problems during the preparation, utilization and further disposal, which is one of the bottlenecks of its practical application. Fundamentally, perovskites are promising materials for generating heterostructures and integrating them with semiconductors due to their soft lattice, which allows for a high tolerance to lattice mismatch [9,10]. Scholars have made considerable efforts to construct a perovskite heterogeneous [11].…”