High-performance perovskite film with superior internal and surface qualities is critical for perovskite solar cells (PSCs) but hardly achievable due to the rapid crystallization rate of perovskite itself. Herein, a novel technique by in situ manipulating perovskite crystal growth and modifying the surface properties is developed using organic passivating agent-assisted polydimethylsiloxane membrane as a facial mask (FM) of perovskites. By placing the perovskite-precursor films with their faces toward the designed FM during thermal annealing, a favorable microenvironment is constructed for incubating high-quality perovskite films with smooth surface, enhanced vertical orientation of (100) plane, and well-adjusted interfacial energy levels. With this versatile FM incubation technique, efficient PSCs for both methylammonium (MA)-based and formamidinium (FA)-MA-Cs mixed perovskite systems are facilely fabricated, delivering excellent humidity/thermal stabilities and promising efficiencies up to 21.4% with an improved open-circuit voltage of 1.15 V in MA-based devices. This study not only provides a facile and efficient approach to rationally manage the perovskite growth process, but also reveals the fundamental characteristics of high-quality perovskite films comprehensively for the construction of efficient and stable PSCs.

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Structural defects in the bulk and on the surface of the perovskite layer serving as trap sites induce nonradiative recombination losses, limiting the performance improvement of perovskite solar cells (PSCs). Herein, we report a trometamol-induced dual passivation (TIDP) strategy to fix both bulk and surface defects of perovskites, where the trometamol molecule can simultaneously act as chemical additive and surface-modification agent. Studies show that trometamol as an additive can effectively reduce ionic defects and enhance the grain size of perovskites through Pb 2+ /−NH 2 coordination bonds and I − /−OH hydrogen bonds. As a surface-modification agent, trometamol further passivates ionic defects at the upper surface of the perovskite layer. As a result of the TIDP approach, a remarkable efficiency augmentation from 17.25% to 19.17% and an optimized thermal stability under inert conditions have been realized. These results highlight the importance of the TIDP strategy in perovskite defect management for excellent photovoltaic properties, facilitating the fabrication of highperformance PSCs.

In this work, the impact of nitrogen doping (N-doping) on the distribution of sub-gap states in amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) is qualitatively analyzed by technology computer-aided design (TCAD) simulation. According to the experimental characteristics, the numerical simulation results reveal that the interface trap states, bulk tail states, and deep-level sub-gap defect states originating from oxygen-vacancy- (Vo) related defects can be suppressed by an appropriate amount of N dopant. Correspondingly, the electrical properties and reliability of the a-IGZO TFTs are dramatically enhanced. In contrast, it is observed that the interfacial and deep-level sub-gap defects are increased when the a-IGZO TFT is doped with excess nitrogen, which results in the degeneration of the device’s performance and reliability. Moreover, it is found that tail-distributed acceptor-like N-related defects have been induced by excess N-doping, which is supported by the additional subthreshold slope degradation in the a-IGZO TFT.

The growth of high-quality perovskite films is complicated by the fact of uncontrollable crystallization pathways from perovskite precursors. During solution processing, extensive undesired nonperovskite products including residual solvate intermediates are produced due to quick solvent evaporation, which will adversely affect the efficiency and stability of perovskite solar cells (PSCs). Herein, we developed a highly efficient phase-transition pathway using a polydimethylsiloxane (PDMS)-based facial mask (FM) incubation technique, which enables significant reduction of the perovskite crystallization rate and depression of perovskite aggregation behavior. A surprising finding reveals that this technique induces complete phase transition from solvate intermediates to the perovskite phase, thereby obtaining phase-pure perovskite film. Meanwhile, a high-quality perovskite film with a shiny smooth surface, decreased defect states, and alleviated lattice strain is achieved after utilizing the FM strategy. Consequently, the target-inverted PSCs deliver a respectable efficiency of ∼21% and superior stability in both shelf storage (over 3700 h with 90% of initial efficiency) and light soaking (over 1000 h with 80% of initial efficiency) conditions. Our work highlights the importance of eliminating residual solvate intermediates to construct high-quality perovskites with excellent phase purity for ongoing production of high-performance perovskite-based optoelectronic devices.