Selective Surface Engineering of Perovskite Microwire Arrays

Abstract

The surface of low‐dimensional perovskites play a crucial role in determining their intrinsic property. Understanding their characteristics and the influence of certain surfaces is valuable in designing functional surface‐engineered structures. Meanwhile, surface passivation can also be applied to stabilize and optimize the state‐of‐the‐art perovskite‐based optoelectronics. Herein, cesium lead bromide (CsPbBr3) microwire parallel arrays are designed and fabricated with specific (100)‐terminated crystal planes, which exhibit excellent photodetection performance with long‐term environment stability >3000 h. Notably, it is uncovered experimentally and theoretically that environmental oxygen can not only passivate the Br‐vacancy‐related trap states on the (100) surface, but also create charge carrier nanochannels to enhance the (opto)electronic properties. The coupling effects between oxygen species and the specific terminated crystal planes of perovskites highlight the importance of surface engineering for designing and optimizing perovskite‐based devices.

Optimized Substrate Orientations for Highly Uniform Metal Halide Perovskite Film Deposition

“…The fitted values for β are 0.86 and 0.76 for v → h and h → v samples, respectively. The higher value for v → h suggests a reduced trap density in the film compared to the h → v sample, indicative of suppressed recombination loss. − This observation aligns with the structural analyses demonstrating the high quality of the v → h sample (Figure S10) and corroborates its device performance, comparable to those of previously reported photoconductor arrays (Table S3).…”

Anti‐Ambipolar Heterojunctions: Materials, Devices, and Circuits

“…[60][61][62] Moreover, in the case of low-dimensional nanomaterials, the quantum confinement effect and surface states play a key role in precisely adjusting the material properties and optimizing device performance. [37,63] In the following subsection, we will present an overview of the materials used in developing anti-ambipolar heterojunctions and their associated utilization principles.…”

“…[98,175] The fitting factor 𝛼 was determined as ≈0.75, suggesting a low recombination rate. [63,175] The photocarrier could regulate the antiambipolar switching characteristics of AATs, showing a new concept for multivalued logic/digital electronic and optoelectronic applications.…”

“…[187] Owing to the high sensitivity of 1D/2D antiambipolar heterostructures, their applicability of image sensing was demonstrated with high-resolution and good operation stability (Figure 15f). [63,98]…”