Haber-Bosch approach, which involves high pressures (10−30 MPa) and temperatures (400−500 °C), large consumption of coal and natural gas to produce hydrogen, leading to excessive emission of carbon dioxide and serious environmental issues. [4][5][6][7] In this regard, developing an efficient, sustainable approach for NH 3 synthesis is urgently desired. Recently, electrochemical nitrogen (N 2 ) reduction reaction (NRR) toward NH 3 synthesis has attracted enormous attention as a feasible approach under ambient conditions. Unfortunately, the low solubility of N 2 in aqueous electrolytes and high fracture energy of the triple bond of N 2 (941 kJ mol −1 ) significantly hinder the improvement of catalytic activity for NRR. [8][9][10] Besides, the energetically favorable hydrogen evolution reaction (HER) as a competitive reaction of NRR would decrease the Faradaic efficiency of N 2 electroreduction to NH 3 , which severely limits the practical applications of NRR toward NH 3 synthesis. [11][12][13][14][15] Alternatively, electrochemical nitrate (NO 3 − ) reduction to NH 3 (NRA) can provide a promising approach for efficient NH 3 synthesis, due to the smaller dissociation energy of NO bond (204 kJ mol −1 ), the higher solubility of NO 3 − in aqueous electrolytes and endowing faster reaction kinetics. [16][17][18][19] Meanwhile, the NRA catalysis can utilize NO 3 − from abundant wastewater or groundwater, offering an avenue to convert NO 3 − into value-added products to restore the imbalance of global nitrogen cycle. Such approach can address the environmental issues caused by the widely existed NO 3 − pollutants in nature that would become a safety hazard for human health, but also offer efficient utilization of NH 3 -related energy sources simultaneously. [20,21] Nevertheless, the NRA electrolysis suffers from large thermodynamic barriers due to its complex eight-electron reaction process and the competitive HER. [22] Tailoring the environments on the catalyst surface to modulate the adsorption of NRA intermediates and suppress the HER rate will hinder the formation of byproducts and boost the selective reduction of NO 3 − to NH 3 . Thus, designing and constructing efficient NRA electrocatalysts with optimized adsorption properties of NO 3 − and reaction intermediates on the catalyst surface are urgently desired.Electrochemical nitrate reduction to ammonia (NRA) provides an efficient, sustainable approach to convert the nitrate pollutants into value-added products, which is regarded as a promising alternative to the industrial Haber-Bosch process. Recent studies have shown that oxygen vacancies of oxide catalysts can adjust the adsorption energies of intermediates and affect their catalytic performance. Compared with other metal oxides, perovskite oxides can allow their metal cations to exist in abnormal or mixed valence states, thereby resulting in enriched oxygen vacancies in their crystal structures. Here, the catalytic activities of perovskite oxides toward NRA catalysis with respect to the amount of oxygen vacanci...

Surface strains are necessary to optimize the oxygen adsorption energy during the oxygen reduction reaction (ORR) in the four‐electron process, but the surface strains regulation for ORR in the two‐electron process to produce hydrogen peroxide (H2O2) is rarely studied. Herein, it is reported that the tensile strained B‐doped Ni nanoparticles on carbon support (Ni‐B@BNC) could enhance the adsorption of O2, stabilize OO bond, and boost the electrocatalytic ORR to H2O2. Moreover, the Ni‐B@BNC catalysts exhibit volcano‐type activity for electrocatalytic ORR to H2O2 as a function of the strain intensity, which is controlled by B content. Among them, Ni4‐B1@BNC exhibits the highest H2O2 selectivity of over 86%, H2O2 yield of 128.5 mmol h–1 g–1, and Faraday efficiency of 94.9% at 0.6 V vs reversible hydrogen electrode as well as durable stability after successive cycling, being one of the state‐of‐the‐art electrocatalysts for two‐electron ORR. The density functional theory calculations reveal that tensile strain introduced by doping B into Ni nanoparticles could decrease the state density of Ni‐3d orbital and optimize the binding energy of OOH* during ORR. A new direction is provided here for the design of highly active and stable catalysts for potential H2O2 production and beyond.

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Electronic devices with tactile and pressure-sensing capabilities are becoming increasingly popular in the automatic industry, human motion/health monitoring, and artificial intelligence applications. Inspired by the natural nanotopography of the cicada wing, we propose here a straightforward strategy to fabricate a highly sensitive tactile sensor through nanotexturing of erected polyaniline (PANI) nanoneedles on a conductive and elastic three-dimensional (3D) carbon skeleton. The robust and compressible carbon networks offer a resilient and conducting matrix to catering complex scenarios; the biomimetic PANI nanoneedles firmly and densely anchored on a 3D carbon skeleton provide intimate electrical contact under subtle deformation. As a result, a piezoresistive tactile sensor with ultrahigh sensitivity (33.52 kPa–1), fast response/recovery abilities (97/111 ms), and reproducible sensing performance (2500 cycles) is developed, which is capable of distinguishing motions in a wide pressure range from 4.66 Pa to 60 kPa, detecting spatial pressure distribution, and monitoring various gestures in a wireless manner. These excellent performances demonstrate the great potential of nature-inspired tactile sensors for practical human motion monitoring and artificial intelligence applications.

Herein, the electronic structure of RhCu nanospheres was optimized and the size of the nanoparticles was reduced by an ultrasonic-assisted hydrothermal method. The performance of electrocatalytic urea synthesis was improved,...