Reliable and efficient continuous-wave (CW) lasers have been intensively pursued in the field of optoelectronic integrated circuits. Metal perovskites have emerged as promising gain materials for solution-processed laser diodes. Recently, the performance of CW perovskite lasers has been improved with the optimization of material and device levels. Nevertheless, the realization of CW pumped perovskite lasers is still hampered by thermal runaway, unwanted parasitic species, and poor long-term stability. This review starts with the charge carrier recombination dynamics and fundamentals of CW lasing in perovskites. We examine the potential strategies that can be used to improve the performance of perovskite CW lasers from the materials to device levels. We also propose the open challenges and future opportunities in developing high-performance and stable CW pumped perovskite lasers.

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Photothermal superhydrophobic coatings are essential for a variety of applications including anti‐icing and light‐driven self‐propelled motion. However, achieving a flexible and durable superhydrophobic coating with high photothermal efficiency and long‐term stability is still challenging. Herein, a facile and eco‐friendly approach to realizing a superhydrophobic coating with excellent flexibility is proposed. The coating is obtained by spraying titanium nitride (TiN) nanoparticles embedded in polydimethylsiloxane (PDMS) solution onto various substrates. A tight binding between the substrate and nanoparticles occurs that offers the coating the mechanical robustness to endure bending, twisting, abrasion, and tape peeling. The water repellency is retained even after 500 cycles of bending–twisting tests. Combined with the micro–nanoscale porous structure of the surface and plasmonic property of TiN nanoparticles, the coating shows excellent superhydrophobicity and high photothermal conversion properties. The equilibrium temperature of the coating is as high as 130 °C at room temperature under 1 W cm−2 of 808 nm near‐infrared laser irradiation. Due to its flexible property, the coating can be easily applied to irregular surfaces, which, together with the excellent anticorrosion, anti‐icing, and defrosting performances, makes it a reliable resource for multifunctional applications. This work offers a novel technological approach to flexible devices, wearable electronics, and smart textiles.

Plasmonic metasurfaces with the photothermal effect have been increasingly investigated for optofluidics. Meanwhile, along with the expanding application of circularly polarized light, a growing number of investigations on chiral plasmonic metasurfaces have been conducted. However, few studies have explored the chirality and the thermal-induced convection of such systems simultaneously. This paper aims to theoretically investigate the dynamics of the thermally induced fluid convection of a chiral plasmonic metasurface. The proposed metasurface exhibits giant circular dichroism in absorption and thus leads to a strong photothermal effect. On the basis of the multiphysical analysis, including optics, thermodynamics, and hydrodynamics, we propose a concept of chiral spectroscopy termed optofluidic circular dichroism. Our results show that different fluid velocities of thermally induced convection appear around a chiral plasmonic metasurface under different circularly polarized excitation. The chiral fluid convection is induced by an asymmetric heat distribution generated by absorbed photons in the plasmonic heater. This concept can be potentially used to induce chiral fluid convection utilizing the chiral photothermal effect. Our proposed structure can potentially be used in various optofluidics applications related to biochemistry, clinical biology, and so on.

Sodium vanadate NaV6O15 (NVO) is one of the most promising cathode materials for sodium-ion batteries because of its low cost and high theoretical capacity. Nevertheless, NVO suffers from fast capacity fading and poor rate capability. Herein, a novel free-standing NVO/multiwalled carbon nanotube (MWCNT) composite film cathode was synthesized and designed by a simple hydrothermal method followed by a dispersion technique with high safety and low cost. The kinetics analysis based on cyclic voltammetry measurements reveals that the intimate integration of the MWCNT 3D porous conductive network with the 3D pillaring tunnel structure of NVO nanorods enhances the Na+ intercalation pseudocapacitive behavior, thus leading to exceptional rate capability and long lifespan. Furthermore, the NVO/MWCNT composite exhibits excellent structural stability during the charge/discharge process. With these benefits, the composite delivers a high discharge capacity of 217.2 mA h g–1 at 0.1 A g–1 in a potential region of 1.5–4.0 V. It demonstrates a superior rate capability of 123.7 mA h g–1 at 10 A g–1. More encouragingly, it displays long lifespan; impressively, 96% of the initial capacity is retained at 5 A g–1 for over 500 cycles. Our work presents a promising strategy for developing electrode materials with a high rate capability and a long cycle life.