Patterned growth of AgBiS₂ nanostructures on arbitrary substrates for broadband and eco-friendly optoelectronic sensing

The patterning of functional nanomaterials shows a promising path in the advanced fabrication of electronic and optoelectronic devices. Current micropatterning strategies are indispensable for post-etching/liftoff processes that contaminate/damage functional materials. Herein, we developed an innovative, low-temperature, post-liftoff-free, seed-confined fabricating strategy that can tackle this issue, thus achieving designated patterns of flower-shaped AgBiS₂ nanostructures at either micro- or macro-scale on arbitrary substrates that are either rigid or flexible. Made of patterned AgBiS₂ nanostructures, the photoconductor shows broadband (320 nm-2200 nm), sensitive (R_peak = 1.56 A W⁻¹), and fast (less than 100 μs) photoresponses. Furthermore, single-pixel raster-scanning and 28 × 12 focal plane array imaging were performed to demonstrate reliable and resolved electrical responses to optical patterns, showcasing the potential of the photoconductor in practical imaging applications. Notably, the patterning process enables strain-releasing micro-structures, which lead to the fabrication of a flexible photodetector with high durability upon over 1000 bending/recovering testing cycles. This study provides a simple, low-temperature, and eco-friendly strategy to address the current challenges in non-aggressive micro-fabrication and arbitrary patterning of semiconductors, which are promising to meet the development of further emerging technologies in scalable and wearable optoelectronic sensors.