Highly Crystalized MAPbX₃ Perovskite Triangular Nanowire Arrays for Optoelectronic Applications

Here, a facile fabrication approach for the high-quality 1D perovskite triangular nanowire (TNW) array synthesis through space-confined effect is reported. A soft stamp containing 1D triangular linear array pattern is used to confine the MAPbX₃ solution and to guide the growth of the nanowires along the prescribed direction with good crystallinity. The further constructed photodetectors based on the obtained MAPbI₃ TNWs exhibit superior photoresponse properties with a responsivity of (125.2 ± 2.5) A W^-1 and detectivity of (2.8 ± 0.8) × 10¹³ Jones at the wavelength of 650 nm. This excellent performance is attributed to the highly crystalline TNW with optical anisotropy and a small asymptotic height, which reduces the probability of the photon reflection and promotes the carrier transport. More interestingly, the increased surface area of the triangular device can present superior flexibility after a couple of thousands of bending cycles. Furthermore, by fabricating 7 × 7 photodetector arrays, the potential image sensor application is demonstrated. The perovskite nanowire fabrication approach is scalable and compatible with current semiconductor manufacturing, which indicates their great potential in broad applications.