Bottom‐Up Templated and Oriented Crystallization for Inverted Triple‐Cation Perovskite Solar Cells with Stabilized Nickel‐Oxide Interface

Abstract

Inverted‐structure perovskite solar cells (PSCs) are known for their superior device stability. However, based on nickel‐oxide (NiOx) substrate, disordered crystallization and bottom interface instability of perovskite film are still the main factors that compromise the power conversion efficiency (PCE) of PSCs. Here, 2D perovskite of thiomorpholine 1,1‐dioxide lead iodide (Td2PbI4) is introduced as a template to prepare 3D perovskite thin film with high crystal orientation and large grain size via a bottom‐up growth method. By adding TdCl to the precursor solution, pre‐crystallized 2D Td2PbI4 seeds can accumulate at the bottom interface, lowering the barrier of nucleation, and templating the growth of 3D perovskite films with improved (100) orientation and reduced defects during crystallization. In addition, 2D Td2PbI4 at the bottom interface also hinders the interfacial redox reaction and reduces the hole extraction barrier on the buried interface. Based on this, the Td‐0.5 PSC achieves a PCE of 22.09% and an open‐circuit voltage of 1.16 V. Moreover, Td‐0.5 PSCs show extremely high stability, which retains 84% of its initial PCE after 500 h of continuous illumination under maximum power point operating conditions in N2 atmosphere. This work paves the way for performance improvement of inverted PSCs on NiOx substrate.

Phase-Engineering of Layered Nickel Hydroxide for Synthesizing High-Quality NiOx Nanocrystals for Efficient Inverted Flexible Perovskite Solar Cells

“…As described in the previous reports, Ni 3+ acceptors generate p-type conductivity in the NiO x thin film. ,, The film’s conductivity was measured using J-V measurements (Figure S8a). As shown in Table S1, the NiO x -NaOH and NiO x -KOH films display higher conductivity; the latter is the best.…”

“…The intercept of the linear regime with the x -axis of the Mott–Schottky plot represents the built-in potential ( V bi ). It is observed that the NiO x -KOH device shows a higher V bi (0.96 V) than that of NiO x -NaOH (0.84 V), which was favorable for interfacial charge separation and extraction. , …”

Buried interface passivation strategies for high-performance perovskite solar cells

“…The organic spacer cation of thiomorpholine 1,1-dioxide hydrochloride (TdCl) has a stronger interaction with PbI 2 compared with FAI, thus making it easier to generate Td 2 PbI 4 2D microcrystals when introduced into the perovskite precursor solution. 125 This is veried by the additional diffraction peaks in XRD and the Stokes shi between lm absorption and emission peaks. As depicted in Fig.…”

DMSO‐Free Solvent Strategy for Stable and Efficient Methylammonium‐Free Sn–Pb Alloyed Perovskite Solar Cells

“…In particular, the D/P treatment triggered a 12 nm blue shift of emission peak (from 981 nm for D/S-treated perovskite to 969 nm for D/P-treated perovskite). [39,40] These data mean that the carrier nonradiative recombination was significantly reduced and the defects were well eliminated by DMPU treatment. Then, the time-resolved photoluminescence (TRPL) spectra were also applied to investigate the carrier lifetime inside these films, as shown in Figure S8 (Supporting Information).…”