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There exist some perovskites materials with no photoluminescence (PL), which will greatly limit the practical applications in photodetection, display and lighting. Here, we achieve an exotic pressure-induced emission (PIE) at a mild pressure of 0.8 GPa from initially non-emissive 2D all-inorganic perovskite Cs3Sb2Br9 quantum dots, when the sample was subjected to external pressure. With the increase of pressure, the PL intensity gradually increases and the emission color transforms from red to green. Combined with subsequent experiments and computations, thus PIE behavior and piezochromism result from the SbBr6 octahedral distortion, accompanied by a structural phase transition from trigonal to monoclinic under pressure. Our work provides a robust strategy to boost the emission efficiency and to construct multi-functional PIE materials with piezochromism in environmentally friendly perovskites, thus facilitating the diverse applications in futural practices.

By using complementary experimental methods including in situ high-pressure single-crystal X-ray diffraction and UV–Vis spectroscopy, the intricate connection between solvatochromism and solvatomorphism has been elucidated in a recent publication [Sobczak & Katrusiak (2024). IUCrJ, 11, 528–537]. The connection was demonstrated for an important pigment – Reichardt's dye – with potential applications in nonlinear optoelectronics and molecular pressure sensor development.

A library of β-enamino diketones was prepared via base-mediated, three-component reaction of 4-hydroxycoumarins with various aromatic/aliphatic amines and β-nitrostyrenes under microwave irradiation conditions to investigate their photochemical properties. Among the prepared compounds, a thiophene derived β-enamino diketone was found to be light-sensitive and to exhibit unique photochromic behavior, that is, positive photochromism in solution and negative photochromism in crystalline phase. In addition, this prepared photochromic compound was further covalently linked to a structure-related, piezochromic β-enamino diketone moiety to explore its potential multi-stimuli responsive properties.

Chromic behavior and electrical conductivity of poly(3-methylthiophene) nanoparticles - coated polyester fabric was investigated by chemical polymerization method. The electrochromic behavior of poly(3-methylthiophene) coated polyester fabrics were measured by digital voltmeter on the samples surface and the reflectance spectra were recorded. The effects of reaction time, temperature, and oxidant concentration on conductivity and other properties of the coated fabric were studied. Scanning electron microscopy confirmed that the surface of fabric has entirely been coated with poly(3-methylthiophene) particles at range of nanometer. Further characterizations were investigated using Fourier transform infrared spectroscopy to provide evidence of forming nanoparticles onto the fabric, UV-Vis absorption spectroscopy, electrical surface resistivity and pressure dependence visible reflectance spectrophotometer measurements. It can be found that the oxidant polymerization has been done physically without any structural changes. Results showed that the increasing of reaction time and temperature (less than 40°C) and oxidant to monomer molar ratio up to 3:1 led to a decrease in the electrical resistance of polymer-coated fabric. Also, the strength of samples was decreased during the polymerization (raw polyester fabric's strength, 23.36 kgf; coated polyester fabric's strength, 19.42 kgf). The blue shift in the reflectance spectra under high pressure represented the piezochromism in poly(3-methylthiophene) nanoparticlescoated polyester fabric.