Porous NiMoO4 Nanosheet Films and a Device with Ultralarge Optical Modulation for Electrochromic Energy-Storage Applications.

Reducing building energy consumption, improving aesthetics, and improving occupant privacy as well as comfort by dynamically adjusting solar radiation are important application areas for electrochromic (EC) smart windows. However, the current transition metal oxides still cannot meet the requirements of neutral coloration and large optical modulation. We report NiMoO4 nanosheet films directly grown on fluorine-doped tin oxide glasses. The as-grown NiMoO4 film not only achieves neutral coloration from transparent to dark brown but also shows an ultralarge optical modulation (86.8% at 480 nm) and excellent cycling stability (99.4% retention of maximum optical modulation after 1500 cycles). Meanwhile, an EC device demonstrating good EC performance was constructed. These results will greatly promote the research and development of binary transition metal oxides for both EC and energy-storage applications, and NiMoO4 films may be an excellent candidate to replace NiO films as ion-storage layers in complementary EC devices with WO3 films as EC layers.

Multifunctional aqueous polyurethanes with high strength and self-healing efficiency based on silver nanowires for flexible strain sensors.

Advanced sensor technology is widely applied in human motion monitoring and research. However, it often encounters problems such as scratches, fractures, and aging, which affect its lifespan and reliability. To address these challenges, we draw inspiration from the inherent self-healing properties of organic biological entities in nature to endow our sensors with self-healing capability. In this work, we constructed a reversible multi-hydrogen-bonded physical crosslinking network and introduced aromatic disulfide bonds into the polyurethane backbone. This design not only achieves a very high mechanical strength of the material, but also efficient self-healing properties. At 80 °C, the tensile strength of the WPU-U2D1 material reached 28.88 MPa, with a fracture elongation of 748.64%, and a self-healing efficiency as high as 99.24%. Based on this material, we successfully prepared a flexible conductive composite film (WPU@AgNW) and applied it to flexible strain sensors. The sensor demonstrated excellent sensitivity and reliability in human motion monitoring (electrical conductivity of 2.66 S cm-1), which provides a new idea for realising the breakthrough of high-performance flexible sensors. These outstanding properties makes it have great potential for application in flexible wearable devices, human-computer interaction, bionic electronic devices and other fields.