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The oxygen evolution reaction (OER) is an important half-reaction in rechargeable metal–air batteries and water splitting devices, and it suffers from slow kinetics due to the multiple step proton-electron coupled process. Therefore, the major challenge for the OER is to develop durable and low-cost electrocatalysts with high catalytic performance. Herein, a ternary metal CoNiFe subacetate nano prism (CoNiFe NP) was synthesized by a one-step hydrothermal method, with the aim of accelerating the water dissociation and improving the reaction rate using the synergy of the ternary metal. The results show that the electrocatalytic performance of the ternary metal CoNiFe layered double hydroxide is significantly improved compared with the binary metal and single metal catalysts. In particular, the overpotential of the prepared CoNiFe NP for the OER at 10 mA cm−2 is as low as 292 mV, and the Tafel slope is 75.6 mV dec−1. This work provides a new platform for the design of medium-entropy electrocatalysts using the interaction of polymetallic components. [ABSTRACT FROM AUTHOR]

Organic and inorganic nitrogen play important roles in plant nitrogen nutrition. However, how the coapplication of organic and inorganic nitrogen affects root growth, plant nitrogen metabolism, and soil nitrogen content is still unclear. Plant shoot and root growth, nitrogen uptake and metabolism, and soil nitrogen content were studied in maize (Zea mays L.) through pot experiments with different nitrogen treatments, including NH4+ -N (Amm), NO3− -N (Nit), NH4+ -N + NO3− -N (Amm + Nit), NH4+ -N + NO3− -N + glutamate-N (Amm + Nit + Glu), and NH4+ -N + NO3− -N + glycine-N (Amm + Nit + Gly). The results show that the shoot nitrogen uptake of maize treated with Amm + Nit + Gly was the highest among all the nitrogen treatments. In addition, the coapplication of glycine and inorganic nitrogen increased glutamine synthetase (GS) activity in the maize leaves, promoted nitrogen metabolism levels, and was conducive to the accumulation of amino acids and soluble protein in leaves. Compared with inorganic nitrogen, glycine combined with inorganic nitrogen increased the total root length and root surface area. A correlation analysis showed that total root length and root surface area had a significant positive effect on nitrogen uptake. When ammonium, nitrate, and glycine were applied together, the content of inorganic nitrogen and total nitrogen in soil was higher than that for other inorganic nitrogen treatments. Therefore, we conclude that glycine combined with inorganic nitrogen can increase soil nitrogen content, promote maize root growth, and thus facilitate nitrogen uptake and metabolism. [ABSTRACT FROM AUTHOR]

Nano bowl-like Co–Co6Mo6C2 coated by N,P co-doped carbon (Co–Co6Mo6C2@NPC) is reported as an electrocatalyst for Zn–air batteries. Co–Co6Mo6C2@NPC only needs an overpotential of 210 mV at 10 mA cm−2 for the OER, and the half-wave potential for the ORR is 0.81 V. In addition, the Co–Co6Mo6C2@NPC based battery shows a large open-circuit voltage of 1.335 V and a maximum power density of 160.5 mW cm−2, as well as good stability. The improved catalytic performance can be ascribed to the co-existence of Co6Mo6C2 and Co species to improve the intrinsic catalytic activity, and the bowl-like nanostructure to facilitate the mass transfer. [ABSTRACT FROM AUTHOR]

Single-atom catalysts with precise structure and tunable coordination nature provide opportunities for developing novel catalytic centers and understanding reaction mechanisms. Herein, hollow Co9S8 polyhedrons with lattice-confined Ru single atoms (Ru-Co9S8) are fabricated. Aberration-corrected scanning transmission electron microscopy and X-ray absorption spectroscopy verify the isolated Ru atoms are confined in Co9S8 to form Co-S-Ru catalytic centers. Theoretical calculations indicate that the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) energy barriers are extensively reduced, and the d-band center of Co9S8 downshifts from the Fermi level, therefore boosting the desorption of O-containing intermediates. Consequently, the Ru-Co9S8 exhibits an ultralow overpotential of 163 mV at 10 mA·cm−2 for OER and could catalyze a rechargeable Zn-air battery with a high-power density of 92.0 mW·cm−2. This work provides a promising approach for designing novel bifunctional catalytic active centers for energy conversion. [ABSTRACT FROM AUTHOR]

Accurate quantification of net primary productivity (NPP) is key to estimating vegetation productivity and studying the global carbon cycle. However, C3 and C4 plants vary in their living environments and potential productivity due to their different photosynthetic pathways. This study thus explored the potential of the near-infrared radiance of vegetation (NIRv,Rad) to track hourly and daily changes in C3 and C4 plants and investigate whether their photosynthetic pathways affect the relationship between NPP and NIRv,Rad. Statistics including long-term spectral data, the growth environment, and physiological indicators were collected using an automatic spectral monitoring system. The vegetation index NIRv,Rad was extracted from the collected spectral data and NPP was calculated using the collected net photosynthetic rate and leaf area index. The results showed that NIRv,Rad can effectively respond to NPP changes in C3 and C4 plants on hourly and daily scales. The NPP–NIRv,Rad relationship on the hourly scale was superior, with R2 values for winter wheat and summer maize of 0.81 and 0.70, respectively. Furthermore, when the accumulation of NPP was equal, the NIRv,Rad of summer maize showed larger changes, indicating that it was more sensitive to NPP change for this species than for winter wheat. Overall, the study demonstrated that NIRv,Rad can serve as an effective proxy indicator of NPP. In addition, this study provides a theoretical basis and scientific guidance for the construction of new simple models and realizing efficient agriculture, as well as a new method for rapid and accurate quantification of the NPP of C3 and C4 plants at geospatial scales in future research. [ABSTRACT FROM AUTHOR]

Development and utilization of hydrogen energy is an effective way to achieve carbon neutrality, only hydrogen production through electrolytic water splitting meets the goal of zero carbon emission. To facilitate the large‐scale commercialization of water splitting devices, the development of highly efficient and low‐cost catalysts to reduce the energy consumption is essential. MoS2 has been regarded as a promising electrocatalyst to replace platinum in hydrogen evolution reaction due to its low price and unique 2D layered structure. However, the poor conductivity and inert basal planes of MoS2 limited its wide‐spread application. Recently, researches have demonstrated that the conductivity and active sites of MoS2 can be improved by heteroatoms doping or constructing of heterogeneous structures. In this review, the recent progress of Mo‐based catalysts are summarized centered on MoS2 based on interface engineering and anion engineering, including MoS2–MoO2, MoS2–Mo2C, MoS2–MoNx, MoS2–MoP, and MoS2–MoSe2. The preparation method, structure, and performance of the catalysts are introduced and the possible mechanism behind the improved catalytic activity are revealed to give readers an overall comprehension on the progress of the Mo‐based electrocatalysts for hydrogen evolution reaction. In addition, an outlook on future opportunities and development directions of Mo‐based catalysts are proposed to facilitate the development of Mo‐based catalysts for hydrogen production. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) to realize low‐cost water splitting is the premise for large‐scale production of hydrogen. The catalytic activity of an electrocatalysts greatly depends on its composition and structure. In this work, we report the preparation of hollow CoS2/MoS2 heterostructure using ZIF‐67 as the precursor. The ratio of Co and Mo are optimized to maximize the synergy of CoS2 and MoS2, due to their specific catalytic activity for OER and HER. The optimized CoS2/MoS2 exhibits good bifunctional catalytic activity in view of its low overpotentials for HER (170 mV) and OER (270 mV), as well as small cell voltage of 1.66 V for overall water splitting. This work provides a facile strategy to controllable fabrication of efficient bifunctional electrocatalysts for renewable energy applications. [ABSTRACT FROM AUTHOR]