Capillary-written single-crystalline all-inorganic perovskite microribbon arrays for highly-sensitive and thermal-stable photodetectors†
In recent times, as a result of its exceptional resistance to moisture and heat, cesium lead bromide (CsPbBr3) has been established as a potential high-performance perovskite material for optoelectronics, which is inclusive of photodetectors and photovoltaics. It has been demonstrated that a perovskite single crystal has major benefits over its thin-film equivalents; nevertheless, the preparation of perovskite crystal arrays for the utilisation of extensive integration is a challenging task. In this paper, we consider a simple crystallisation system, being a capillary-written system to enable the growth of single crystal microribbon arrays (MRAs) directly from a precursor solution. It is demonstrated by microstructure characterisation that CsPbBr3 MRAs are good-quality single crystals with highly-aligned crystal packing and smooth surfaces. The band-edge photoluminescence (PL) is exceptionally resilient and has a lengthy PL life of ∼62 ns. An exceptional photo-response having a particularly quick 99 μs response time and a 2496 A W−1 ultra-high responsivity is exhibited by photodetectors which are built upon these MRAs. The fact that the as-fabricated photodetectors maintain 90% of their commencing performance following 100 days of constant stress testing under ambient conditions under an illumination of 450 nm, showing exceptional operational stability, is noteworthy. A significant step towards the large-area growth of high-quality perovskite MRAs is presented by this work. This supplies favourable opportunities to build high-performance optoelectronic and nanophotonic systems.