Management of perovskite intermediates for highly efficient inverted planar heterojunction perovskite solar cells

Abstract

The management of perovskite intermediates to construct perovskite films with uniform perovskite crystals and controlled surface morphology was introduced.

Simultaneous Cesium and Acetate Coalloying Improves Efficiency and Stability of FA0.85MA0.15PbI3 Perovskite Solar Cell with an Efficiency of 21.95%

“…As reported by Tang et al, by adding a small amount of PbAc 2 into perovskite precursor solution, the grain size of MAPbI 3 films could be enlarged and defects could be reduced, and finally, the device performance is improved. Similarly, as reported by Xia et al, the Ac − in methylammonium acetate (MAAc) also improves the crystallization of the perovskite films and performances of PSCs. Thus, Cs + or Ac − alloying has been proved to be a feasible and effective way for achieving PSCs with high efficiency and stability.…”

“…Figure b shows the magnified XRD pattern for (110) peaks; there is an obvious reduction in the full width at half maximum (FWHM) of the peak (110) of perovskite film with 1.2 mol% CsAc alloying compared with that of control film, confirming the improved crystallinity for the alloyed perovskite film. In addition, the (110) peaks of FA 0.85 MA 0.15 PbI 3 films slightly shift to higher 2 θ values with increasing CsAc concentration (Figure b), suggesting a lattice contraction effect due to smaller ionic radius of Cs + (0.167 nm) and Ac − (0.162 nm) comparing with that of FA + (0.19–0.22 nm) and I − (0.220 nm), respectively . The element substitution is benefit to stabilizing the crystal structure because Goldschmidt tolerance factor of perovskite is improved, which is expected to stabilize ideal black phase of FAMA perovskites through closely packed atom arrangement …”

Engineering Halide Perovskite Crystals through Precursor Chemistry

“…In the case of the additives with low boiling point and high volatility, the removal of additives could be triggered during the initial solidification process. For example, because of the facile removal of methylammonium acetate (MAAc) (see Figure a), the accelerated perovskite crystallization kinetics during the spin coating process was induced, which improved the perovskite morphology . A similar strategy has been reported to result in compact and smooth perovskite thin films by employing volatile NH 4 Cl .…”

Management of Crystallization Kinetics for Efficient and Stable Low‐Dimensional Ruddlesden–Popper (LDRP) Lead‐Free Perovskite Solar Cells

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Much effort devoted in photovoltaic field, including material optimization, structural optimization, and interface engineering, has allowed the power conversion efficiency (PCE) of perovskite solar cells (PSCs) quick increase to 23.3%, [18] which is comparable to state-of-the-art commercial photovoltaic techniques, such as silicon and other thin-film solar cells. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Much effort devoted in photovoltaic field, including material optimization, structural optimization, and interface engineering, has allowed the power conversion efficiency (PCE) of perovskite solar cells (PSCs) quick increase to 23.3%, [18] which is comparable to state-of-the-art commercial photovoltaic techniques, such as silicon and other thin-film solar cells.…”

“…As shown in Figure 1a, we clearly observed that the LDRP BA 2 MA 3 Sn 4 I 13 perovskite films from DMSO (Lewis theory) have poor surface coverage, which is different from previous work demonstrating that the intermediate phase 3DMSO-SnI 2 formed by the Lewis base DMSO and SnI 2 can retard the rapid reaction between SnI 2 and MACl and achieve the high-quality perovskite films. [13] However, the films based on MAAc appeared the highest roughness of 31.906 nm (19.288 nm for DMSO based film) as a result of a large excess of MA + ( Figure S1, Supporting Information). When MAAc (ion exchange process) was used as precursor solvents, the intermediates BAMASn-Ac was formed rapidly and then dense LDRP BA 2 MA 3 Sn 4 I 13 perovskite films can be produced by ion exchange between I − and Ac − (Figure 1b).…”