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The synthesis of ammonia through the Haber–Bosch process has indirectly led to significant CO2 emissions. Electrochemical synthesis of ammonia from NOx under ambient conditions is key for achieving resource conservation and nitrogen cycle equilibrium. Herein, the state-of-the-art of the NOx reduction reaction to ammonia (NOxRR-to-NH3) is totally reviewed, with aspects on aqueous and nonaqueous electrolytes. In this context, the functional mechanism is briefly outlinedin aqueous and nonaqueous media, respectively, and the electrocatalyst design as well as the electrolyte modification in both solvents is summarized in detail. N2 reduction in ionic liquids is presented, which provides meaningful suggestions for the electrocatalytic NOxRR-to-NH3 process in such media. The principal challenges faced by this field were discussed in the review. The primary obstacles are the disfavourable chemical kinetics, which includes the inert dynamics of NOx and hydrogen evolution reaction during the reduction process. Secondly, developing cost-efficient and performance-superior electrocatalysts and electrolyte systems is urgent for addressing such issues. At last, the outlook for future investigation is proposed. [ABSTRACT FROM AUTHOR]

Hierarchical metal grids are proven to be a promising solution for achieving high‐performance flexible transparent electrodes (FTEs) due to their significantly enhanced conductivity without noticeably sacrificing transparency. This work develops a one‐step mask‐free line‐shaped laser lithography by separated pulse laser ablation to efficiently fabricate large‐area FTEs composed of hierarchical metal grids, namely microscale grids interconnected with aligned nanowire arrays. The linewidth of aligned wires is highly controllable from the nanometer scale far beyond the diffraction limit (<λ/10) to the micrometer scale. This work experimentally studies the overall performance of FTEs to provide a guideline for selecting the layout and feature sizes of hierarchical metal grids. Hierarchical metal grids with 50 nm nanowires aligned inside the microscale grids show outstanding optoelectronic properties and mechanical stability, with sheet resistance of 4.6 Ω sq−1, transmittance of 82.9%, and a tiny increase in sheet resistance less than 4% after 1000 cycles of bending tests. These results prove that the line‐shaped laser lithography technique is a facile, low‐cost, and high‐throughput fabrication method for high‐performance FTEs. [ABSTRACT FROM AUTHOR]

The rapid development of flexible electronics greatly promotes personalized health monitoring and thereupon spawns diverse wearable electronic devices. As a key functional component of flexible electronics, flexible strain sensor receives tremendous research effort, and is widely applied to various areas such as electronic skin, human–machine interaction, and structural health monitoring. Carbon‐based materials including carbon nanotubes (CNTs), carbon black, and graphene are employed as functional materials in this paper to be mixed with the elastic polydimethylsiloxane (PDMS) matrix via the solution blending method. A bridge‐island structure is designed due to its unique structure and dispersion ability, enabling the derived sensor with both good stretchability of 100% and sensitivity of 8.99. The results offer a potential strategy for addressing the difficulties of sensitivity‐stretchability tradeoff originating from the flexible strain sensors prepared with single carbon‐based filler material and other similar strain sensors. Moreover, the realization of an intercommunication system between the flexible strain sensor and a mobile phone via NRF52805 Bluetooth communication chips can monitor various body motions in real time, demonstrating a promising prospect for building remote health monitoring and management systems. [ABSTRACT FROM AUTHOR]

Full mineralization of organic pollutants is a tough task with existing technologies. Even if all conventional energies and extremes are exhausted, high-temperature wastewater treatment is not worth the loss from the perspective of energy. Solar engineering holds promise for the full mineralization of organic pollutants to tackle the global fossil energy shortage. Here, we report solar engineering for full mineralization and efficient solar utilization. The solar energies and spectrum were fully utilized to initiate the solar heat and solar electricity. Two energies were applied to trigger the thermochemical and electrochemical oxidation of the organic pollutants. Our study bridges the gap between the energy and environment towards efficient solar utilization and effective water treatment. As a proof-of-concept study, this demonstrates a solar engineering of full phenol mineralization in wastewater. A record phenol mineralization rate was achieved to reach an oxidation rate of 98% and COD of 93% under a constant current density of 50mA/cm2 at 150°C. UV and HPLC were used to detect the intermediate products during variable time intervals. The results showed that the intermediate products are composed of maleic acid, hydroquinone and p-benzoquinone. In the extreme high temperature (90°C), the solar oxidation time and pathway are greatly altered. The reaction rate constant at 150°C is about 11 times than that at 90°C. More solar heat significantly reduces the activated energy of the pollutant oxidation and lowers the potential of electrolysis. [ABSTRACT FROM AUTHOR]