(111)‐Dominated Perovskite Films by Antisolvent Engineering

Abstract

Fabricating perovskite films with a dominant crystal orientation is an effective path to realizing quasi‐single‐crystal perovskite film, which can eliminate the fluctuation of the electrical properties in films arising from grain‐to‐grain variations, and improve the performance of perovskite solar cells (PSCs). Perovskite (FAPbI3) films based on one‐step antisolvent methods usually suffer from chaotic orientations due to the inevitable intermediate phase conversion from intermediates of PbI2•DMSO, FA2Pb3I8•4DMSO, and δ‐FAPbI3 to α‐FAPbI3. Here, a high‐quality perovskite film with (111) preferred orientation ((111)‐α‐FAPbI3) using a short‐chain isomeric alcohol antisolvent, isopropanol (IPA) or isobutanol (IBA), is reported. The interaction between IPA and PbI2 leads to a corner‐sharing structure instead of an edge‐sharing PbI2 octahedron, sidestepping the formation of these intermediates. With the volatilization of IPA, FA+ can replace IPA in situ to form α‐FAPbI3 along the (111) direction. Compared to randomly orientated perovskites, the dominantly (111) orientated perovskite ((111)‐perovskite) exhibits improved carrier mobility, uniform surface potential, suppressed film defects and enhanced photostability. PSCs based on the (111)‐perovskite films show 22% power conversion efficiency and excellent stability, which remains unchanged after 600 h continuous working at maximum power point, and 95% after 2000 h of storage in atmosphere environment.

Impacts of PbI2 on high-efficiency perovskite solar cells: exploring intercalation orientations and defects

“…Furthermore, experimental observations identify the (0 0 1) plane of PbI 2 and the (1 1 1) plane of perovskite within the perovskite absorbers with excess PbI 2 . [54][55][56] Regarding the (1 2 0) plane of the two-dimensional PbI 2 boundary, it is also reasonable for regional growth by saturating the interfacial dangling bonds, although its detection within the mixed system proves challenging. Differing in terms of interfacial atoms and the intercalating orientations of layered PbI 2 , the possible heterointerface models are constructed (models before and after relaxation are presented in Fig.…”

High-Performance Lead-Free Layered-Perovskite Photodetectors and Bipolar Transistors by Solvent Engineering

“…Metal-halide perovskite is a remarkable photoelectric material known for its unique characteristics such as high absorption coefficient, long carrier lifetime, and ultralong carrier diffusion length. , This makes it highly attractive for developing efficient optoelectronic devices. Photodetectors, which convert optical signals into electrical signals, hold great application and scientific research value in both military and civil fields. − However, most semiconductor materials used for photodetector applications are expensive and require stringent manufacturing processes and conditions.…”

Study of the Heat‐Induced Degradation Mechanism in PbI2‐Excess Perovskite Solar Cells

“…[3] Lin et al and Sun et al fabricated ultrastable regular-structure PSCs using excess PbI 2 . [18,19] The aforementioned discussion indicates that photodecomposition may not be the only reason for the accelerated degradation of PbI 2 -excess PSCs.…”