Phys.org September 30, 2022 Researchers in China fabricated a bio-solar cell consisting of a four-species microbial community by mimicking the ecological structure of marine microbial ecosystems. The four-species microbial community was assembled into a spatial-temporally compacted cell using conductive hydrogel as a sediment-like anaerobic matrix, forming a miniaturized bionic ocean-battery. The battery directly converts light into electricity with a maximum power of 380 μW. It stably operated for over one month. They demonstrated such ecological structure consisting of primary producer, primary degrader, and ultimate consumers is essential for achieving high power density and stability. According to the researchers the photoelectric conversion […]
Tag Archives: S&T China
Researchers unveil mystery inside lithium oxygen batteries
Phys.org September 30, 2022 Researchers in China prepared an integrated air electrode with highly ordered channels. They observed morphological composition and distribution of Li2O2 inside the real air electrode. The results showed that the toroidal Li2O2 was constrained by the channel size and exhibited a larger diameter on the separator side at high currents. The coupling effects of charge transfer impedance and concentration polarization on sudden death were analyzed in-depth at low and high currents. The growth model suggested that toroidal Li2O2 exhibited a high dependence on the electrode surface structure. They proposed a new route where the Li2O2/electrode interface […]
Optical encryption method based on single pixel imaging and metasurface holography
Nanowerk September 26, 2022 The precise control of phase, amplitude, polarization, metasurface holography provides a flexible platform for light modulation, optical encryption. The process of image reconstruction by single pixel imaging is similar to a form of encoding and decoding, which is realized by calculating the correlation between a series of modulation patterns and their corresponding intensity signals. Researchers in China proposed an optical encryption scheme based on spatial multiplexing metasurface, which depends on the combination of holographic technology and single pixel imaging technology. In the encryption scheme, the image transmitted by single pixel imaging based on metasurface was used […]
Hygroscopic polymeric gels: Collecting freshwater and energy from atmospheric moisture
Phys.org September 19, 2022 Atmospheric moisture exploitation (AME) technology has emerged as a promising alternative solution to improve the unbalanced supply-and-demand relationship between reducing essential resources (particularly energy and freshwater) and growing population. Hygroscopic polymer gels (HPGs) are regarded as desirable materials for AME owing to their considerable hygroscopicity, highly tunable structures, and easy integration with functional components. In a review article researchers in China cover an in-depth overview of the up-to-date progress in HPGs used for AME. They have presented the hygroscopic mechanisms of HPGs, state-of-the-art construction strategies, and illustrated relationships between structures and properties. They have included cutting-edge […]
Researchers improve mechanical properties of aluminum/steel joints
Phys.org September 5, 2022 To join aluminum to steel researchers in China proposed an innovative hybrid resistance spot-laser welding process. The welding current distribution and the weld structure were optimized to produce a thin and uniform intermetallic layer with its thickness below 1.2 μm. The faying interface morphology of aluminum and steel dissimilar materials was changed from a traditional flat surface to an interface with a deep bulge into the aluminum weld. The presence of a weak bonding area around the periphery of the joint facilitated the crack initiation and rapid propagation. Laser spot welding process inhibited rapid propagation of […]
Harvesting energy – drop by drop
Nanowerk August 25, 2022 In this review article researchers in China summarized the recent developments in droplets-driven nanogenerators for effective energy scavenging. They included an extensive discussion about the device structures from the material selection and output performance aspects. They gave a brief discussion on the applications of droplet-based nanogenerators and outline the future possibilities via the current improvement in designs and fabrication strategies that have been introduced by the field. According to the authors water droplet harvesting as a sustainable energy resource has become a forward-looking step to meet the future demand for green energy. The emerging potential of […]
Novel smart material enables high-performance and reliable light control of droplets
Nanowerk August 24, 2022 Light control of droplets enables remote and contactless control with remarkable spatial and temporal accuracy. However, their performance, and reliability are challenging. Researchers in China have developed a new smart material with photo-induced charge regeneration capability, enabling light control of droplets with superior performance and reliability. The smart material contains three core components: micro-size liquid metal particles with superior photothermal and thermally conductive properties; polyvinylidene fluoride trifluoroethylene copolymer with excellent ferroelectric and mechanical behaviors; and micro-pyramidal structures and low-surface-energy coatings of fluorinated SiO2 nanoparticles for enhancing the superamphiphobicity. The photo-induced charged surfaces (PICSs) possess a superior […]
Scientists identify liquid-like atoms in densely packed solid glasses
Nanowerk August 22, 2022 Extensive studies on the structure and relaxation dynamics of glasses have constructed the current classical picture: glasses consist of some ‘soft zones’ of loosely bound atoms embedded in a tightly bound atomic matrix. Recent experiments have found an additional fast process in the relaxation spectra, but the underlying physics of this process remains unclear. Researchers in China combined extensive dynamic experiments and computer simulations and found that the fast relaxation is associated with string-like diffusion of liquid-like atoms, which are inherited from the high-temperature liquids. Even at room temperature, some atoms in dense-packed metallic glasses can […]
The entanglement of two quantum memory systems 12.5 km apart from each other
Phys.org August 16, 2022 Researchers in China have reported the establishment of post selected entanglement between two atomic quantum memories physically separated by 12.5 km. They created atom-photon entanglement in one node and sent the photon to a second node for storage via electromagnetically induced transparency. They harnessed low-loss transmission through a field-deployed fiber of 20.5 km by making use of frequency down-conversion and up-conversion. The final memory-memory entanglement was verified to have a fidelity of 90% via retrieving to photons. According to the researchers their experiment makes a significant step forward toward the realization of a practical metropolitan-scale quantum […]
Acoustics researchers develop novel underwater carpet cloak
Phys.org July 28, 2022 Aided by a reflecting surface, the acoustic carpet cloak has become one of the most practically feasible invisibility devices. However, due to the difficulty in the realization of ideal material parameters, the underwater carpet cloaks could only work for a small incident angle. Researchers in China designed an underwater carpet cloak using a three-component metafluid composed of syntactic foam, steel, and water. The syntactic foam, which is synthesized from epoxy resin and hollow glass microspheres, exhibits lower mass density and higher sound velocity relative to water. By periodically embedding the syntactic foam and steel rods in […]