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Multifunctional materials are an attractive research area. Organic‐inorganic hybrid perovskites are widely used in the design of these materials due to their rich properties and flexible composition. It is easy to obtain more photoelectric properties by introducing chiral groups as ligands. In this work, we synthesized chiral one‐dimensional organic‐inorganic hybrid perovskites, namely (R/S‐3‐HP)PbBr3 (1R/1S) (3‐HP=3‐hydroxy‐piperidine). The enantiomer compounds undergo reversible phase transition at 349/336 K. Under the excitation light of 339 nm, 1R and 1S have a wide emission peak at 635 nm, showing orange light. In addition, the indirect bandgap is 3.29 eV and the SHG intensity is comparable to that of KDP. This work provides a way to design multifunctional chiral perovskite materials. [ABSTRACT FROM AUTHOR]

S-doped Na2Ti6O13@TiO2 (S-TTO) core–shell nanorods, with exposed anatase TiO2 {101} facets, were synthesized by a facile calcination method. It was found that the addition of thiourea as the sulfur precursor was beneficial for the formation of anatase TiO2 with a better crystallinity and the doped sulfur atoms favorably stabilized the anatase structure. The substitution of Ti4+ by S6+ in the lattice of S-TTO gave rise to the visible light response and increased the amount of active groups typically as a hydroxyl radical adsorbed onto the catalyst surface. With the formation of the Ti–O–S bond, partial electrons could be transferred from S to O atoms. The electron-deficient S atoms might capture e− and thus inhibit the recombination of photogenerated electron–hole pairs. Meanwhile, a closely contacted interface was formed between Na2Ti6O13 and anatase TiO2, resulting in a nanoscale heterojunction structure to speed up the separation rate of photogenerated charge carriers. The exposed anatase {101} facets could act as possible reservoirs of the photogenerated electrons, yielding a highly reactive surface for the reduction of O2 to O2Ṗ− and thus the decrease of recombination probability of electron–hole pairs. In addition, the anisotropically shaped titanate nanorods provided a pathway for the quick transport of charge carriers throughout the longitudinal direction. The combined effects of S doping, nano-heterojunction formation and morphology engineering led to an obviously enhanced photocatalytic performance for the degradation of methylene blue (MB) solution under visible light irradiation. The corresponding photocatalytic mechanism was investigated and discussed in detail. The present work may provide an insight into the fabrication of delicate composite photocatalysts with excellent performance. [ABSTRACT FROM AUTHOR]

In this work, the single crystal to single crystal (SCSC) transformations in three mononuclear copper complexes [Cu L 2 2 ]Cl 2 ·2H 2 O ( 1 ), [Cu L 1 2 Cl 2 ] ( 2 ), and [Cu L 2 2 ]Cl 2 ·4H 2 O ( 3 ) ( L 1 = di-2-pyridyl ketone, L 2 = di(pyridin-2-yl)methanediol) are realized by the irreversible dehydration and hydration reaction of L 1 and L 2 . Dark purple crystal 1 is obtained by self-assembly of L 1 and CuCl 2 ·2H 2 O in solvothermal reactions, in which the carbonyl group of L 1 undergoes a hydration addition reaction to form L 2 . On heating, 1 transforms to 2 by dehydrating water accompanied by the change of the color and coordination octahedron of Cu II ions. In a saturated water vapor environment, 2 can absorb six water molecules and transform to 3 with the same color and coordination environment with 1 but different lattice water. The SCSC process from 2 to 3 is reversible: 3 can transform back to 2 on heating like that of 1 . Chroma rewritable behaviors in the structural transformation of the complexes make them visually identifiable temperature or water probes.

Multifunctional materials have always been an attractive research area, but how to combine multiple excellent properties in one compound remains a considerable challenge. Organic-inorganic hybrid compounds are widely used in the design of such materials due to their rich properties and flexible assembly. Herein, two new manganese(II)-based organic-inorganic hybrid compounds, (C 6 NH 16 ) 2 MnBr 4 ( 1 ) and (C 7 NH 18 ) 2 MnBr 4 ( 2 ), are prepared by the solution method. Compounds 1 and 2 both emit extremely strong green light under UV excitation, with high quantum yields of 45.93 and 50.98%, respectively. In addition, reversible solid-state phase transitions and obvious switchable dielectric properties are shown at 378/366 and 361/352 K, respectively. The coexistence of the dual stimulus-response characteristics of temperature and light in compounds 1 and 2 opens a new path for exploring more multifunctional phase transition materials.