Strain analysis and engineering in halide perovskite photovoltaics

Abstract

Halide perovskites are a compelling candidate for the next generation of clean energy harvesting technologies thanks to their low cost, facile fabrication and outstanding semiconductor properties. However, photovoltaic device efficiencies are still below practical limits and long-term stability challenges hinder their practical application. Current evidence suggests that strain in halide perovskites is a key factor in dictating device efficiency and stability. Here, we outline the fundamentals of strain within halide perovskites relevant to photovoltaic applications and rationalize approaches to characterize the phenomenon. We examine recent breakthroughs in eliminating the adverse impacts of strain, enhancing both device efficiencies and operational stabilities. Finally, we discuss further challenges and outline future research directions for placing stress and strain studies at the forefront of halide perovskite research. An extensive understanding of strain in halide perovskite is needed, which would allow effective strain management and drive further enhancements in efficiencies and stabilities of perovskite photovoltaics.

Spectral Stable Blue-Light-Emitting Diodes via Asymmetric Organic Diamine Based Dion–Jacobson Perovskites

“…Furthermore, we propose two other possible scenarios: (i) incorporation of asymmetric large cations results in stronger interactions between DPDA and the inorganic framework, which leads to perovskite grains with a more rigid structure; 50 − 52 (ii) organic cation-assisted high quality growth of perovskite grains with uniformly ordered cations surrounding the DJ perovskite grains and suppressed local strains (induced by grain boundaries) leads to suppression of ion migration. 52 − 54 The rigidity of the perovskite structure can be inferred from our XRD results ( Figure S1b ). When DPDA is incorporated, the perovskite peak at 31.1° shifted to a lower angle of ∼30.8° (0.04 M) corresponding to a total shift of ∼0.3° signifying the expansion in the lattice parameter.…”

Strain Engineering: A Pathway for Tunable Functionalities of Perovskite Metal Oxide Films

“…While many studies has been undertaken and tremendous progress has been made in the synthesis and application of such materials, there are still many open questions related to the roles of strain, defect, interface, microstructure, and heterogeneity at different length scales on the physical properties of the materials. The recent review article published by Liu et al summarizes the progress and challenges on this front admirably [ 129 ].…”

Reversible Pressure‐Dependent Mechanochromism of Dion–Jacobson and Ruddlesden–Popper Layered Hybrid Perovskites

“…[27] Under higher pressures, the compressed inorganic perovskite lattice relaxes through two competing processes, namely M-X bond tilting or M-X bond contraction (Figure 1c, right), [7,28,29] which directly affect the optoelectronic properties. [13,28] While previous work primarily involved the behavior of hybrid perovskites under high pressure, [13,28] it is of great importance to study effects in mild pressure regimes (<1 GPa), since induced levels of strain are comparable with polaron effects, [30,31] chemical (i.e., conformational) strain, [32,33] or strain due to lattice mismatches, [33,34] especially in 2D/3D perovskite composites. [35] In that regard, the behavior under mild pressures may serve as a powerful tool for controlling the properties of these materials in a manner comparable to other processes inducing internal strain.…”