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The water evaporation rate of 3D solar evaporator heavily relies on the water transport height of the evaporator. In this work, a 3D solar evaporator featuring a soil capillary‐like structure is designed by surface coating native balsa wood using potassium hydroxide activated carbon (KAC). This KAC‐coated wood evaporator can transport water up to 32 cm, surpassing that of native wood by ≈8 times. Moreover, under 1 kW m−2 solar radiation without wind, the KAC‐coated wood evaporator exhibits a remarkable water evaporation rate of 25.3 kg m−2 h−1, ranking among the highest compared with other reported evaporators. The exceptional water transport capabilities of the KAC‐coated wood should be attributed to the black and hydrophilic KAC film, which creates a porous network resembling a soil capillary structure to facilitate efficient water transport. In the porous network of coated KAC film, the small internal pores play a pivotal role in achieving rapid capillary condensation, while the larger interstitial channels store condensed water, further promoting water transport up more and micropore capillary condensation. Moreover, this innovative design demonstrates efficacy in retarding phenol from wastewater through absorption onto the coated KAC film, thus presenting a new avenue for high‐efficiency clean water production. [ABSTRACT FROM AUTHOR]

Pore modulation of carbon structures with low cost is of great importance for promoting the large-scale application of advanced supercapacitors. Herein, we innovatively propose a method for the directional preparation of hierarchical porous carbon materials using carbon aerogels assisted by mantis shrimp shells. The chitosan-based aerogel realizes self-assembly crosslinking in the mantis shrimp shell template possessing ordered pore arrays, with the template removed to obtain carbon materials with the corresponding pore structure after pre-carbonization, which is conducive to the full mixing of subsequent activators. The elimination of CaCO3 in the template and the further activation of carbon materials promote the formation of a porous structure. Thanks to the reasonable pore size distribution, high specific surface area and N/O doping of the carbon materials, a high specific capacitance of 401 F g−1 (0.5 A g−1) is achieved as an electrode material in a three-electrode system with 6 M KOH electrolyte. The pore distribution of the carbon materials at 0.5 and 0.8 nm enables the symmetric supercapacitors with the EMIMBF4 ionic liquid electrolyte to achieve an ultra-high energy density of 82.5 W h kg−1 (437.5 W kg−1). Further, the capacitance characteristics and ion diffusion rate are revealed in depth by Trasatti and Dunn's method as well as ion diffusion kinetic analysis. In addition, the transient distribution of electrolytes with different pore structures is simulated by COMSOL Multiphysics, which confirms that the hierarchical porous structure prepared with the assistance of mantis shrimp shells is more beneficial to the rapid diffusion of ions. [ABSTRACT FROM AUTHOR]

Electrolyte engineering advances Li metal batteries (LMBs) with high Coulombic efficiency (CE) by constructing LiF-rich solid electrolyte interphase (SEI). However, the low conductivity of LiF disturbs Li+ diffusion across SEI, thus inducing Li+ transfer-driven dendritic deposition. In this work, we establish a mechanistic model to decipher how the SEI affects Li plating in high-fluorine electrolytes. The presented theory depicts a linear correlation between the capacity loss and current density to identify the slope k (determined by Li+ mobility of SEI components) as an indicator for describing the homogeneity of Li+ flux across SEI, while the intercept dictates the maximum CE that electrolytes can achieve. This model inspires the design of an efficient electrolyte that generates dual-halide SEI to homogenize Li+ distribution and Li deposition. The model-driven protocol offers a promising energetic analysis to evaluate the compatibility of electrolytes to Li anode, thus guiding the design of promising electrolytes for LMBs. The low conductivity of LiF disturbs Li+ diffusion across solid electrolyte interphase (SEI) and induces Li+ transfer-driven dendritic growth. Herein, the authors establish a mechanistic model to decipher how the SEI affects realistic Li plating in high-fluorine electrolytes. [ABSTRACT FROM AUTHOR]