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The strategic regulation of the electronic properties and coordination environment of single‐atom sites through the integration of metal nanoclusters emerges as a promising route to enhance the oxygen reduction reaction (ORR) performance of Fe–N–C materials. Here, a catalyst (FeIn–NC) is successfully developed in which Fe–N–C materials encapsulate Fe–In alloy nanoclusters, and it shows excellent ORR activity and durability under alkaline conditions, with a high half‐wave potential of 0.924 V (vs RHE) and a zinc–air battery power density of 202.1 mW cm−2, superior to commercial Pt/C catalysts. Theoretical calculations unravel that the synergistic interaction between the Fe–In alloy and the FeN4 single‐atom site modifies the electronic structure and charge distribution at the FeN4 site, thereby enhancing the electrocatalytic activity and durability of the ORR. Potential‐dependent microkinetic modeling (MKM) further discloses the ORR mechanisms on the identified FeN4 sites. This work provides a viable strategy for the ORR improvement of Fe–N–C materials via p‐block metal‐based alloy nanoclusters. [ABSTRACT FROM AUTHOR]

The silent yet ubiquitous natural evaporation of water stores immense energy, and electrical double layers from the hydrolysis of oxygen-containing functional groups are the key to power generation at the solid–liquid interface of evaporation. However, slow ion diffusion in evaporation-driven water transport limits efficient energy harvesting for electricity generation. In contrast to the typical homogeneous interfacial oxygen-containing functional groups (OCGs), we present a high-performance wood-based interfacial evaporation-driven nanogenerator (W-IENG) with significantly distributed OCG gradients, which is constructed through a rational process design using bioinspired self-assembled multilayer nanofiber membranes. Based on the abundance of reactive OCGs contained in wood derivatives, our design is simply constructed by gradient reduction in the number of hydrolysis sites of OCGs using different materials. In particular, this porous interface exhibits lower charge transfer resistance and higher ionic conductivity. As a result, the power density of our device is approximately 7.5 times higher than the average value of previously reported W-IENGs. These findings provide novel insights into the optimization of efficient evaporative power generation systems through the functional coupling of evaporation interfaces using the OCG gradient and facilitate the effective utilization of energy in the natural environment. [ABSTRACT FROM AUTHOR]

Composite materials are widely used in aerospace, automotive industry and medical equipment, where most of the structural parts are made of fiber laminates. Rotary braiding is one of the most important methods to prepare composite preforms. The ordinary rotary braided preforms have low porosity and dense yarns, but are single-layer structures after molding, which do not meet the needs of most applications. To solve the problem that traditional laminates are prone to delamination, this paper designs a flat cross-linked braiding process for the preparation of multilayer-interlocking composite panels. The carrier trajectory is analyzed, and the spatial coordinate system of the braided chassis is established by combining the effect of the end traction system on the morphology of the preform yarns. The numerical model of the preform is initially obtained by using cubic B-spline curve fitting, and an algorithm for gathering yarns towards the fabric center is proposed to optimize the numerical model. Experimental samples of flat cross-linked preforms are prepared according to the braiding process, and the reliability of the optimization algorithm is verified by comparing the yarn coordinates of the experimental samples with those of the optimized numerical model. [ABSTRACT FROM AUTHOR]

Solar interfacial evaporation offers an economical and efficient solution to the global shortage of freshwater resources, and the introduction of the side evaporation surface brings new insights into its efficiency. However, water vapour accumulation slows the evaporation speed at high evaporation rates, and further improvements in its performance have reached a bottleneck. Herein, we develop a zero-carbon tower-type integrated solar evaporator (TIE), which relies solely on solar photothermal power at the bottom to achieve an effective water vapour escape cycle by natural convection, eliminating the need for forced convection (e.g. fins, ducts, etc.). Meanwhile, the hierarchical evaporation surface of the TIE constructed by highly oriented fiber bundles achieves efficient interfacial sunlight absorption and continuous water evaporation in seawater environments. Interestingly, we show that the evaporation rate with this natural gain strategy reaches 5.7 kg m−2 h−1 under one sun intensity, which is about 32% higher than the average level of the reported three-dimensional solar evaporators. The solar chimney framework overcomes the application limitations of solar evaporators. Our strategy holds the potential to enable the implementation of efficient water evaporation systems to provide a water vapour escape cycle by natural convection without the assistance of other energy losses. [ABSTRACT FROM AUTHOR]