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For obtaining environment-friendly and efficient green corrosion inhibitors， the photinia leaf extracts (PTF) were prepared by distilled water reflux method.The corrosion inhibition performance of PTF on Q235 steel in 1 mol/L hydrochloric acid was studied using electrochemical tests， weight loss tests， scanning electron microscopy and other methods.Results showed that as a mixed corrosion inhibitor， PTF could effectively inhibit the corrosion of Q235 steel in hydrochloric acid medium.The corrosion inhibition efficiency increased with the increase of PTF concentration and decreased with the increase of solution temperature.Furthermore， the inhibition efficiency of 4 g/L PTF was 87.99%at 293 K.The results of adsorption isotherm model showed that PTF could spontaneously adsorb on the surface of Q235 steel through physical effects， which conformed to the Langmuir single-layer adsorption model.

Covalent organic frameworks (COFs) have emerged as compelling interface optimizer candidates for competent perovskite solar cells (PSCs). However, there is a notable absence of rationally designed COFs tailored for perovskite and hole transporting layers (HTLs). Herein, an unreported one-dimensional (1D) triarylamine-based covalent organic framework (COF) {[(TPA)2(TPB)1]–C＝N–} with active amino groups was first synthesized. To anchor COF on the perovskite surface and manipulate the interface hole transportation, this 1D COF was salified with hydrogen halides to produce {[(TPA)2(TPB)1]–C＝N–-X} (COF-X; X = Cl, Br, and I). The ammonium terminals (–NH3+) can coordinate with perovskite via strong ionic interaction. The backbone units of triphenylamine (TPA) and N,N,N′,N′-tetraphenylbenzidine (TPB), renowned for their superior hole extracting and transporting properties, can enhance the hole mobility of the perovskite film from 1.02 to 3.72 cm2 V−1 s−1. Consequently, the optimal device achieved a power conversion efficiency (PCE) of 23.58% and an impressive open-circuit voltage (VOC) of 1.181 V. Additionally, the unencapsulated devices retained 90.8% and 89.2% of their initial efficiencies after atmospheric storage over 4800 hours and continuous illumination over 500 hours, respectively. [ABSTRACT FROM AUTHOR]

A series of single phase (Na1/2Eu1/2)xCa1−xCu3Ti4O12 (x = 0, 0.01, 0.05, 0.1, 0.2, 0.3, 0.35, 0.4 and 0.45) ceramics with different doping amounts were successfully prepared by high temperature solid-state reaction method. The microstructure, ion valence, and dielectric properties of the ceramics were systematically studied. The results indicated that with the increase of Na+ and Eu3+ ions concentration in (Na1/2Eu1/2)xCa1−xCu3Ti4O12 ceramics, Na and Eu elements accumulated at the grain boundaries of ceramics, thereby increasing the insulation of grain boundaries and effectively reducing the dielectric loss of the ceramics. However, the presence of Cu+ in (Na1/2Eu1/2)xCa1−xCu3Ti4O12 (x ≥ 0.3) ceramics with high doping content could affect the polarization mechanism inside the ceramics and improve their dielectric properties. The dielectric constant of (Na1/2Eu1/2)0.3Ca0.7Cu3Ti4O12 ceramics was as high as 25 282, with a dielectric loss of 0.061 (at room temperature and 10 Hz), and it had good dielectric stability. [ABSTRACT FROM AUTHOR]

α‐phase formamidine lead iodine (α‐FAPbI3) as a competitive candidate to pursue high‐performance perovskite solar cells (PSCs) suffers from the weakness of random nucleation and disordered growth in chasing high‐grade polycrystalline films. Here, single‐crystal seeds crystallization (SCSC) method is proposed to obtain high‐quality α‐FAPbI3 perovskite films for the first time. Six single‐crystals seeds (CsPbBr3, CsPbI3, FAPbBr3, FAPbI3, MAPbBr3, and MAPbI3) are employed to regulate α‐FAPbI3 perovskite crystallization. These seeds act as nucleation sites and allow the perovskite to grow directly. The rapid crystallization significantly improves the crystallinity of perovskite films with uniform morphology, large grain size, and less defects. Of particular note, FAPbBr3 seed prefers to grow α‐FAPbI3 epitaxially from FAPbBr3@PbI2 heterostructure through a halogen anion exchange process. The average grain size of FAPbBr3‐perovskite film is boosted to 2.6 µm, and the trap density reduced by 11 times. The resultant FAPbBr3‐PSCs achieve a maximum power conversion efficiency (PCE) of 23.84% with a high open‐circuit voltage of 1.18 V. The unencapsulated PSC retains 91% of the initial PCE after 3000 h of storage at ≈30–50% relative humidity and preserves 98.5% of the original value after 155 h illumination with maximum power point tracking. [ABSTRACT FROM AUTHOR]

CsPbBr3 quantum dots (QDs) prepared through traditional hot‐injection and room temperature reprecipitation methods are usually hexahedral (nanoplate/cube) and green‐emitting. These methods severely obstruct the development of blue perovskite‐based light‐emitting diodes (PeLEDs) because the resultant QDs always suffer unachievable morphology regulation. Here, highly efficient blue‐emitting rhombic dodecahedron CsPbBr3 QDs (CsPbBr3 <12> QDs) are obtained by regulating morphological transformation for the first time through a novel and facile sequential post‐treatment strategy. Hydrobromide (‐NH3+) with stronger adsorption energy promotes the morphology transform of QDs from nanoplate to cube by substituting oleylamine in the first step. Then, polar solvent vapor eliminates PbX64− and led to the (112) crystal plane of the cube QDs being exposed, which is effectively stabilized by ‐NH3+ to realize morphology transition from cube to the dodecahedron. Highly efficient 12‐faceted dodecahedrons are endowed with significantly enhanced photoluminescence quantum yield of 89.8% at 476 nm as well as uniform size distribution and mono‐dispersity. The target blue PeLEDs achieve the maximum external quantum efficiency of 6.6% (480 nm) and excellent spectrum stability. This study provides a new strategy to prepare blue‐emitting CsPbBr3 <12> QDs by delicate control toward the growth and polyhedron process of crystal. [ABSTRACT FROM AUTHOR]