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Random lasing in liquid crystals is an emerging field that combines the unique optical properties of liquid crystals with the fascinating behaviour of random lasers. This review provides a comprehensive analysis of the basic principles of random lasing, highlights the unique properties of liquid crystals, and examines strategies for optimizing laser performance in this context. Furthermore, we discuss the promising applications of liquid crystal-based random lasers across diverse fields, including telecommunications, display technologies, and sensing. Despite significant progress, challenges persist in enhancing the reliability and operational stability of these systems. To address these issues, we outline potential research directions, such as integrating random lasers into new technologies and developing novel liquid crystal materials. These initiatives have the potential to drive breakthrough innovations in photonics and related fields. [ABSTRACT FROM AUTHOR]

Visible light photocatalysis offers a green and sustainable approach to wastewater treatment and environmental remediation. This study focuses on the synthesis of fibrous silica titania (FST) via a green method and comprehensively evaluates its photocatalytic performance compared with Ti3AlC2 powder. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed superior crystallinity and unique lamellar structures in FST, contributing to its enhanced photocatalytic activity. The FST catalyst achieved remarkable degradation efficiencies of 93% for MB and 96% for rhodamine B (RB) under visible light, outperforming the bare Ti3AlC2 powder. This promising performance is attributed to FST's narrow band gap (∼2.98 eV), high surface area, and minimal photogenerated charge carrier recombination. Kinetic studies showed excellent agreement with pseudo-first-order kinetics, with R2 values of 0.9801 and 0.988 for MB and RB, respectively. Reusability tests demonstrated sustained efficiency, with degradation rates remaining above 80% after four cycles. GC-MS analysis identified intermediates formed during photocatalytic degradation, ultimately converting them into harmless products, i.e., CO2 and H2O. These findings highlight FST as an economical, sustainable, and efficient photocatalyst for organic pollutant degradation compared to Ti3AlC2. [ABSTRACT FROM AUTHOR]

We propose an innovative design for interdigital transducers (IDTs), enabling phase modulation of surface acoustic waves (SAWs) with a dislocated electrode structure. By designing the size and arrangement of these dislocated IDTs, a novel type of Airy SAWs can be generated, exhibiting self-accelerating, self-bending, and self-healing characteristics. The acceleration of the generated Airy SAW is 0.081 cm−1. Furthermore, particles and bubbles can be precisely manipulated using the generated Airy SAW. The proposed dislocated IDTs could be used for generation of many other types of SAWs, hence holding great promise for applications including SAW shaping, particle manipulation/sorting, and acoustic sensing/detection. [ABSTRACT FROM AUTHOR]

A BODIPY dye functionalized with uracil-ethynyl groups at the 2,6-positions supramolecularly polymerized into J-aggregates directed by intermolecular H-bonds and featured intense absorption and resonant fluorescence. The alignment of J-aggregated chromophores in a thin film was achieved by a rubbing method and polarized photoluminescence with a dichroic ratio up to 14.3 was obtained. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (PVSCs) show promising applications in terrestrial power plant systems irrespective of curved surfaces, but still suffer from low efficiencies and poor stabilities. Here, we report a synergetic strategy of combining bromine (Br) and cetyltrimethylammonium chloride (CTAC) additives to passivate both bulk and surface defects, leading to improved performance and stability of flexible PVSCs. Incorporation of Br suppresses the formation of halide vacancies in the perovskite bulk, while CTAC further modifies the film surface with reduced defects and enhanced hydrophobicity features. As a result, flexible PVSCs with efficiencies over 18% are achieved with high reproducibility, compared to the control devices with efficiencies about 17%. Our flexible PVSCs present excellent ambient stability against moisture, keeping over 90% of the initial efficiency after exposure to 90% humidity for about 170 hours. Our work offers a facile and universal strategy for the fabrication of high performance and stable flexible PVSCs. [ABSTRACT FROM AUTHOR]

Photoelectric resistive random access memory (RRAM) is a promising optoelectronic technology that is being developed to overcome the Von Neumann bottleneck and improve the computing and access performance of current computer systems. In this work, an ultra-stable broadband photoelectric tunable RRAM device based on PbS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) hybrid materials was demonstrated. The device exhibits a long retention capability (>104 s), a high ON/OFF current ratio (104), fast response time (170 ns), cycle-to-cycle consistency, impressive environmental stability (>90 days) and flexibility. Multilevel data storage can be achieved through the appropriate setting of a series of compliance currents. In addition, the SET voltage of the device shows a broadband tunability from the ultraviolet (405 nm) to the near infrared (1177 nm). Furthermore, conductive atomic force microscopy (CAFM) measurements confirm that the formation and rupture of Ag conducting filaments are responsible for the resistive switching behavior. This study paves the way toward the development of next-generation high-density data storage technology and broadband photoelectric memory and computer technologies. [ABSTRACT FROM AUTHOR]

A high quantum yield, tunable band gap, and high color purity of perovskite nanocrystals make this class of materials attractive for electronic and optoelectronic applications in devices including solar cells, photodetectors, and light emitting diodes. Herein, we report for the first time the facile synthesis of perovskite nanocrystals based on (CH3NH3)1−xCsxPbBr3. The emission properties, photoluminescence and stability of the mixed-cation perovskite nanocrystals have been intensively studied, which are significantly related to the content of cesium in the composition. The as-obtained (CH3NH3)1−xCsxPbBr3 nanocrystals were employed as the emission layer in perovskite light emitting diodes, and the device fabricated with the optimized perovskite nanocrystals (Cs doping x = 0.3) showed a maximum luminescence of 24 500 cd m−2, nearly ten-fold higher than those for the previous reported perovskite devices based on MAPbBr3 nanocrystals. This study opens a new avenue for the fabrication of efficient perovskite nanocrystals and provides great potential of developing perovskite LEDs based on mixed-cation perovskite nanocrystals. [ABSTRACT FROM AUTHOR]

Solution processed quantum dots (QDs) were employed as semiconductor layers in low operating voltage nonvolatile memory devices where graphene oxide (GO) was embedded as a charge storage element. Ambipolar PbSe QD layers have the ability to intrinsically transport holes and electrons, which provides an opportunity for the GO layers to trap both holes and electrons efficiently, resulting in bidirectional threshold voltage shifts after the program/erase operations are applied. The memory exhibited a large memory window (ΔVon∼ 6 V) and a long retention time (＞104 s) under low program/erase operating voltages of ±25 V. The magnitude of ΔVon is controlled not only by programming/erasing voltages (VP/E) but also by the bias voltage (VDS), where ΔVon shows a quadratic function to VP/E and linearly depends on VDS. The QD based GO-floating-gate memory devices supply a facile route for fabricating flexible devices with low-cost large-scale integration. [ABSTRACT FROM AUTHOR]

Active plasmonics has been an interesting and important topic recently. Here we demonstrate the all-optical, polarization-insensitive tunable manipulation of a hybrid system that integrates a silver nanorod array with photoresponsive liquid crystals. The large-area plasmonic nanorod arrays are fabricated by laser interference lithography and ion milling. By covering a layer of photoresponsive liquid crystals, tunable control of plasmon resonance is achieved under an external light pump. The silver nanorod array also enables the homeotropic alignment of the liquid crystals, which makes the all-optical tuning behavior polarization-insensitive. With its advantages of cost-effective fabrication, easy integration, all-optical control, and polarization-insensitivity, the hybrid system could be valuable in many nanophotonic applications. [ABSTRACT FROM AUTHOR]

Correction for 'Broadband photoelectric tunable quantum dot based resistive random access memory' by Zhiliang Chen et al., J. Mater. Chem. C, 2020, 8, 2178–2185, DOI: 10.1039/C9TC06230K. [ABSTRACT FROM AUTHOR]

Correction for ‘Bright and efficient light-emitting diodes based on MA/Cs double cation perovskite nanocrystals’ by Bing Xu et al., J. Mater. Chem. C, 2017, 5, 6123–6128. [ABSTRACT FROM AUTHOR]