Flexible transparent conductive electrodes (TCEs) are widely applied in flexible electronic devices. Among these electrodes, silver (Ag) nanowires (NWs) have gained considerable interests due to their excellent electrical and optical performances. Ag NWs with a one-dimensional nanostructure have unique characteristics from those of bulk Ag. In past 10 years, researchers have proposed various synthesis methods of Ag NWs, such as ultraviolet irradiation, template method, polyol method, etc. These methods are discussed and summarized in this review, and we conclude that the advantages of the polyol method are the most obvious. This review also provides a more comprehensive description of the polyol method for the synthesis of Ag NWs, and the synthetic factors including AgNO3 concentration, addition of other metal salts and polyvinyl pyrrolidone are thoroughly elaborated. Furthermore, several problems in the fabrication of Ag NWs-based TCEs and related devices are reviewed. The prospects for applications of Ag NWs-based TCE in solar cells, electroluminescence, electrochromic devices, flexible energy storage equipment, thin-film heaters and stretchable devices are discussed and summarized in detail.

Traffic noise is on the rise worldwide. Birds have been reported to decrease in number and diversity near highways. This could be indirectly caused by traffic if birds avoid overall poorer habitat quality near highways or directly if birds actively avoid noisy conditions. To test whether traffic noise directly affects birds' spatial preferences, we designed a preference test where zebra finches (Taeniopygia guttata) could move freely between noisy and quiet aviaries that only differed in the type of noise playbacks. During playback of high amplitude traffic noise recorded near from highways (5-15 m), birds spent significantly more time in the quieter aviary. Such spatial preferences were not observed during playbacks of moderate amplitude traffic noise recorded further away (200-400 m). Our result provides experimental support for the growing notion that traffic noise itself rather than the presence of vehicles may suffice to deter birds from busy roads.

Rare Earth Upconversion nanoparticles (UCNPs) are a type of material that emits high-energy photons by absorbing two or more low-energy photons caused by the anti-stokes process. It can emit ultraviolet (UV) visible light or near-infrared (NIR) luminescence upon NIR light excitation. Due to its excellent physical and chemical properties, including exceptional optical stability, narrow emission band, enormous Anti-Stokes spectral shift, high light penetration in biological tissues, long luminescent lifetime, and a high signal-to-noise ratio, it shows a prodigious application potential for bio-imaging and photodynamic therapy. This paper will briefly introduce the physical mechanism of upconversion luminescence (UCL) and focus on their research progress and achievements in bio-imaging, bio-detection, and photodynamic therapy.

Ocean occupies about 71% of the global surface area and contains 97% of the total water on the earth. Ocean waves are regarded as one of the most promising renewable energy sources, but it is quite difficult to harvest such low‐quality and low‐frequency energy due to the technology limitations of traditional electromagnetic generators. In this work, a type of arc‐shaped triboelectric nanogenerator (AS‐TENG) with internal rolling structure is designed to harvest low‐frequency water wave energy. The freestanding roller with flexible surfaces can scroll freely with low friction along the arched track under external triggering, generating induced current between the complementary electrodes. The arc‐shaped design facilitates the high‐density integrating of multiple TENG units and effective packaging for potential large‐scope applications. One AS‐TENG can deliver an output power density of 5.47 W m−3 under regular triggering, while a power density of 2.34 W m−3 is achieved for an AS‐TENG array under real water wave triggering of 1.2 Hz. Moreover, through harvesting water wave energy by the AS‐TENG array, self‐powered temperature sensing and wireless transmission systems have been successfully constructed. This work demonstrates huge application prospects of the AS‐TENGs toward large‐scale ocean blue energy harvesting and environmental monitoring.

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