Two-dimensional molybdenum disulfide (MoS2) is a promising electrode material for supercapacitors, attributing to attractive physical properties, outstanding electrical properties, and ultrahigh exposed surface area. However, MoS2 bulk suffers from low capacity due to the overlaying of the layers and the poor electric conductivity. Covalent functionalization of MoS2 is a promising, yet challenging, approach to overcome the drawbacks and boost electrochemical performance. Here, we report a series of sandwich-like 4-aminophenyl functionalized MoS2/polyaniline (MoS2–NH2/PANI) nanosheets by in situ growth of PANI on MoS2–NH2 templates. The optimized MoS2–NH2/PANI nanosheets express a high capacitance of 326.4 F g–1 at 0.5 A g–1 and a superior rate retention of 63.1% when the current density increased from 0.5 A g–1 to 1000 A g–1 in a three-electrode system. Impressively, the corresponding symmetric supercapacitors deliver an electrochemical cycling stability with 96.5% retention after 10000 cycles at 5 A g–1. Our strategy of covalent linking PANI onto functional MoS2 provides a feasible approach to improve the electrochemical performance of MoS2-based materials for energy storage.

Solution processing of perovskite solar cells (PSCs) is highly promising for the high‐throughput production of cost‐effective devices. Although PSCs have achieved great advances in power conversion efficiency, challenges still remain in the reproducibility of high‐quality perovskite thin film with simultaneously improved precursor solution stability. Here, a reactive inhibition strategy by introducing diethyl (hydroxymethyl) phosphonate (DHP) in perovskite precursor solution is successfully employed to improve the stability of precursor solution and the performance of corresponding device. DHP inhibits the reactivity of the iodide and formamidinium ions through multiple chemical bonds, ensuring the stability of the precursor solution. In addition, due to chelation interaction of Pb2+ with the oxygen of PO in DHP, the DHP in the perovskite film improves the film quality with desired stoichiometry by reducing the defects and the content of lead iodide. The DHP‐doped precursor solution and corresponding devices show excellent performance reproducibility and super stability under ambient conditions for more than 50 days, which illustrates the commercial feasibility for scalable fabrication.

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Although two-dimensional perovskite devices are highly stable, they also lead to a number of challenges. For instance, the introduction of large organic amines makes crystallization process complicated, causing problems such as generally small grain size and blocked charge transfer. In this work, imprint assisted with methylamine acetate were used to improve the morphology of the film, optimize the internal phase distribution, and enhance the charge transfer of the perovskite film. Specifically, imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate, thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase. In this case, the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability. Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.

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