Strain Relaxation for Perovskite Lattice Reconfiguration

Abstract

The perovskite lattice strain correlating to its physical chemistry not only impacts the optoelectronic properties but also the long‐term stability. The relaxation of perovskite lattice strain has been recognized as an important pathway to improve photovoltaic performance and broaden the application scope. With the growth of research interest and the thriving of synthetical approaches in strain engineering, it is particularly necessary to summarize the current strategies to give an in‐depth understanding of the relaxation of lattice strain. Herein, the milestones in strain relaxation studies are summarized and the theoretical simulation and methodological approach to correlate the crystal structure and physical properties at an atomic level is outlined. This perspective provides fundamentals to theoretically predict and experimentally measure the strain relaxation effect and suggests design principles and synthetical strategies for tackling the lattice strain issue for perovskites.

Mechanical and Electrical Comparative Studies of Widely Utilized Solar Perovskite Thin Films via Scanning Probe Microscopy

“…Tong et al proposed that ferroelectric polarization, generated by the deformation of inorganic framework, can be the plausible source of hysteresis . Additionally, the orientation of A-site (dipolar) cations can be easily rotated under external stimuli, resulting in the augmentation of strain in perovskite crystal. ,, In this work, Cs 0.2 FA 0.8 PbI 2.25 Br 0.75 and Cs 0.05 FA 0.81 MA 0.14 PbI 2.55 Br 0.45 exhibit fwhm broadening at low vicinity wavenumbers, as a result of Pb – I vibration. Such vibration possibly stabilizes A-site dipole interaction.…”

Defect-Passivated Photosensor Based on Cesium Lead Bromide (CsPbBr3) Perovskite Quantum Dots for Microbial Detection

“…When the lattice parameters were calculated using Bragg’s law, a decrease in the a -axis and an increase in the c -axis were observed in the parylene coating (parylene-F and parylene-C). Internal strain occurred within the lattice structure when the perovskite had halide vacancy, and XRD peaks shifted to a lower angle . Therefore, these results indicate that the halides of the parylene films interact with the bromide vacancies of perovskite, and the strain caused by halide vacancies is reduced .…”

Structure‐Function Relationship of Highly Reactive CuOx Clusters on Co3O4 for Selective Formaldehyde Sensing at Low Temperatures

“…Specifically, for pure Co 3 O 4 , the lattice constant a is now 8.101 Å, which is closer to the reference value, as expected due to temperature‐induced lattice‐strain relaxations. [ 48 ] When adding Cu, the lattice constant a still increases, suggesting that some substitutionally incorporated Cu ions are still present, but lower expansion hints at Cu migration to the surface, similarly to other Cu/Co 3 O 4 materials after repeated heating cycles. [ 49 ] As a result, annealing likely enriches the Co 3 O 4 surface with Cu‐related species, which is favorable for surface‐active processes (e.g., gas sensing or heterogeneous catalysis), as explained below.…”