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Since the emergence of inorganic–organic hybrid perovskites a few years ago, there have been many promising achievements in the field of green and red perovskite light‐emitting diodes (PeLEDs). Nevertheless, the performance of blue‐light PeLEDs faces challenges. In this work, the unique synergy obtained by introducing two different ligands to successfully form quasi‐2D perovskite films, which can exhibit stable blue‐light emission, is utilized. The fabricated PeLEDs have a maximum external quantum efficiency of 2.62% and a half lifetime (T50) of 8.8 min. Meanwhile, the electroluminescence spectrum with its peak located at 485 nm, demonstrates improved stability by applying different voltage bias. The finding in this work offers a new way to achieve steady blue PeLEDs with high performance. [ABSTRACT FROM AUTHOR]

Abstract: A photoresponsive organogel surface (POS), which integrates characteristics of the photothermal property of Fe3O4 nanoparticles and the low hysteresis feature of lubricant‐infused organogels, is shown. A photothermally induced dynamic temperature gradient can be formed rapidly at the location of near‐infrared‐light irradiation (NIR) on POS with suitable Fe3O4 nanoparticles content. Thus, various droplets (e.g., water, glycerol, ethylene glycol, propylene glycol, and ethanol) can be transported effectively and nimbly (e.g., along desired trajectories with controllable velocity and direction, even run uphill and deliver solid particles). This work reveals a synergistic effect between the asymmetrical droplet deformation and the inside Marangoni flows, which forms a unique driving force for droplet transport with high efficiency. This finding offers insight into the design of novel responsive interface materials for droplet transportation, which would be significant for laboratory‐on‐a‐chip contexts, mass transportation, and microengines. [ABSTRACT FROM AUTHOR]

Temperature‐adaptive variable emissivity reflectors offer an electricity‐free and environmentally friendly cooling strategy, holding substantial potential to improve the global energy landscape. However, challenges associated with unoptimized solar absorptance can lead to overcooling or overheating when the modulation of infrared emittance is held constant, thereby increasing extra energy consumption. Herein, a temperature‐adaptive variable emissivity reflector based on W‐Mg co‐doped VO2 (W‐Mg‐VER) is proposed, engineered to optimize solar absorptance (αL = 0.40) while maintaining effective infrared emittance modulation (Δɛ = 0.69) near ambient temperature. To maximize year‐round energy savings in regions experiencing significant daily temperature fluctuations, W‐Mg co‐doped VO2 is employed to reduce solar absorptance by modifying electron occupancy in the V 3d orbital and expanding the optical bandgap. Outdoor experiments have validated the remarkable temperature management and energy‐saving capabilities of the W‐Mg‐VER, facilitated by its seamless transition between radiative cooling and heat‐retaining modes. Numerical simulation indicates that a W‐Mg‐VER roof covering 100 m2 would save 152.9 GJ of energy annually in locations with significant daily temperature variations. Moreover, W‐Mg‐VER demonstrates robust performance, exhibiting less than 1% degradation in emittance tunability and solar absorptance after 10 000 cycles. This approach provides valuable insights and practical guidance for significantly enhancing global energy savings. [ABSTRACT FROM AUTHOR]