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 PO 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.
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.
The paper has done an empirical study in five large department stores of Baoding to explore the mechanism of influencing factors on customer loyalty. This study finds that traffic facilities, product value, reputation factor, Consumer individual factor, service function quality and shopping environment are six main dimensions in customer loyalty influencing dimensions.And then, taking Baoding department store and supermarket as an example, a factor extraction model based on Support Vector Machines for classification (SVC) is constructed. Experiments show scale of park, having shopping card of this store and product breed is the important ones on customer loyalty.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.