Strain-free hybrid perovskite films based on a molecular buffer interface for efficient solar cells

Abstract

Strain is ubiquitous in perovskite based photovoltaic cells, but can be hardly well released in most perovskite films, which usually impose adverse effect on devices’ performance and lifetime. Here, a...

Zn2+ ion doping for structural modulation of lead-free Sn-based perovskite solar cells

“…To verify the strain in the lattice between pristine and 5% Zn, grazing incidence XRD was performed. 25,28,31 We selected grazing incidence angles of 0.5°, 2.5°, 5.0°, and 7.5°and showed the (100) planes of the control and Zn-5. As shown in Fig.…”

“…Recently, the local lattice strain affecting the optoelectronic properties of perovskite lms has attracted attention. [24][25][26][27][28][29][30][31] Local lattice strain is caused by lattice distortion of the octahedron in a perovskite lm [24][25][26] or mismatched thermal expansion coefficients of perovskite and its substrates. 28,31 Saidaminov et al reported that the local lattice strain in a single cation/halide perovskite facilitates the formation of vacancies.…”

“…[24][25][26][27][28][29][30][31] Local lattice strain is caused by lattice distortion of the octahedron in a perovskite lm [24][25][26] or mismatched thermal expansion coefficients of perovskite and its substrates. 28,31 Saidaminov et al reported that the local lattice strain in a single cation/halide perovskite facilitates the formation of vacancies. 26 They also reported that the mixed cation and halide can suppress defect formation via strain relaxation.…”

Pure 2H phase MoSe2 nanosheets promote the formation of a porous PbI2 film and modulate residual stress for highly efficient and stable perovskite solar cells

“…Key driving forces for the differences in volume contraction are the coefficient of thermal expansion (CTE) a mismatch between perovskite film and ETL. 56 It is reported that the expansion coefficient of the PVK film is 6.1 Â 10 À5 K, which is larger than that of SnO 2 (4.0 Â 10 À6 K). 26 When PVK film cools down after thermal annealing, the contraction of the PVK film is limited by the underlying SnO 2 substrate, resulting in depth-dependent crystal lattice deformation within the PVK film.…”

Direct In Situ Conversion of Lead Iodide to a Highly Oriented and Crystallized Perovskite Thin Film via Sequential Deposition for 23.48% Efficient and Stable Photovoltaic Devices

“…Organic–inorganic hybrid perovskites have become promising optoelectronic materials due to their high carrier mobility, tunable direct band gap, low exciton binding energy, and long carrier diffusion length. − The power conversion efficiency (PCE) of perovskite solar cells (PSC) has rapidly climbed from 3.8 to 25.7% in the past decade. − The preparation methods of PSC mainly include spin-coating, ,,− vapor deposition, and thermal evaporation . Among them, the spin-coating method is the most widely used, and it can be divided into a one-step solution method , and a sequential deposition method. − In the sequential deposition method, perovskite films are obtained by the reaction of lead halide films (such as PbI 2 ) with organic halide solutions (such as formamidine iodide and methylammonium iodide). Compared with the one-step method, the sequential deposition method is reproducible and more easily forms vertically grown perovskite crystals .…”