The preparation of high‐quality perovskite films with low grain boundaries and defect states is a prerequisite for achieving high‐efficiency perovskite solar cells (PSCs) with good environmental stability. An effective additive engineering strategy has been developed for simultaneous defect passivation and crystal growth of CsPbBr3 perovskite films by introducing 1,3,5‐triazine‐2,4,6‐triamine (melamine) into the PbBr2 precursor solution. The resultant melamine–PbBr2 film has a loose, large‐grained structure and decreased crystallinity, which has a positive effect on the crystallization process of the perovskite as it retards the crystallization rate as a result of the interaction between melamine and lead ions. Additionally, the passivation by melamine gives a high‐quality CsPbBr3 perovskite film with fewer grain boundaries, lower defect densities, and better energy level matching is achieved by multistep liquid‐phase spin‐coating, which greatly suppresses the nonradiative recombination resulting from the defects and promotes charge extraction at the interface. A champion power conversion efficiency as high as 9.65 % with a promising open‐circuit voltage of 1.584 V is achieved for PSCs with an architecture of fluorine‐doped tin oxide/c‐TiO2/m‐TiO2/melamine‐added CsPbBr3/carbon‐based hole‐transporting layer. Furthermore, the unencapsulated melamine‐added CsPbBr3 PSC shows superior thermal and humidity stability in ambient air at 85 °C or 85 % relative humidity over 720 h.

The carrier recombination loss induced by defects, imperfect contact as well as energy level barriers at buried interface severely restricts the greater advancement of comprehensive performance of perovskite solar cells...

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Ferroelectric hysteresis loops, remanent polarization, coercive field, and leakage current characteristics were investigated by increasing the film thickness (from 103 nm to 401 nm) of predominantly (117)-oriented Bi3.15Nd0.85Ti3O12 films. The thickness dependence of the coercive fields shows log coercive field vs. log thickness with a slope of approximately −0.65, which is characteristics of the Kay–Dunn scaling law. The films exhibited very low leakage current on the order of 10−7A/cm2 at an applied electric field of 100 kV/cm. Without a discernible thickness-dependence behavior, the leakage current characteristics, including both Schottky emission and space-charge-limited conduction, were well described by a modified Schottky contact model.

All-inorganic CsPbBr3 perovskite solar cells (PSCs) without hole-transport materials (HTMs) have attracted widespread attention because of their significant environmental stability. However, the poor quality of perovskite film and the energetics...

Nd 3+ /Zr 4+ -cosubstituted bismuth titanate (BNTZ x , x = 0, 0.05, 0.1, 0.3, and 0.5) thin films have been fabricated by chemical solution deposition and their polarization hysteresis loops, leakage current, and capacitance butterfly loops investigated. Results show that, at Zr content of x = 0.1, both capacitance and remanent polarization can be greatly improved. The BNTZ 0.1 film also exhibits fatigue-free, excellent leakage current characteristics (I % 9.44 9 10 À9 A) at applied voltage of 3 V. High-quality c-axis-oriented BNTZ x = 0.1 films with improved electrical properties were fabricated; this finding supports the feasibility of engineering polarization rotation in ferroelectric bismuth titanate (as suggested theoretically by Roy et al. in Appl. Phys. Lett. 102:182901, 2013).

The direct‐lit mini LED backlight LCD module can utilize ultra‐fine local dimming technology. This approach can realize not only the thinning of backlight unit, but also more refined dynamic control, improving the dynamic contrast of liquid crystal display. As displays continue to develop toward thinness, the number of required LED chips has increased significantly, causing cost and energy consumption issues. The industry usually uses H: P value (OD/LED pitch) to describe the relationship between the cost and thickness of the backlight module. In this work, mini LED technology was researched and applied. Firstly, a blue light angular bidirectional optical film was applied. By controlling the thickness and refractive index of the multilayer film, an effect of reflecting a small angle and transmitting a large angle of blue light was realized, which increased the irradiation range of a single LED. In this way, the H: P value can be reduced from 0.6 to 0.3. Then top shielding structure of the secondary package was used to expand the light‐emitting angle of the mini LED chips, which reduced the H: P value from 0.64 to 0.48. Finally, the two schemes were combined to bring the H: P value to 0.24. This design reduced the thickness of the module under low‐cost conditions and reached the most advanced level in the industry.

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