Solar‐driven evaporation is regarded as a sustainable wastewater treatment strategy for clean water recovery and salt condensation. However, achieving both high evaporation rate and long‐term stability remain challenging due to poor thermal management and rapid salt accumulation and blocking. Here, a T‐shape solar‐driven evaporator, composed of a surface‐carbonized longitudinal wood membrane (C‐L‐wood) is demonstrated as the top “” for solar harvesting/vapor generation/salt collection and another piece of natural L‐wood as the support “” for brine transporting and thermally insulating. The horizontally aligned micro‐channels of C‐L‐wood have a low perpendicular thermal conductivity and can effectively localize the thermal energy for rapid evaporation. Meanwhile, the brine is guided to transport from the support L‐wood (“”) to the centerline of the top evaporator and then toward the double edge (“”), during which clean water is evaporated and salt is crystallized at the edge. The T‐shape evaporator demonstrates a high evaporation rate of 2.43 kg m−2 h−1 under 1 sun irradiation, and is stable for 7 days of the outdoor operation, which simultaneously realizes clean water evaporation and salt collection (including Cu2+, CrO42−, Co2+), and achieves zero‐liquid discharge. Therefore, the T‐shape design provides an effective strategy for high performance wastewater treatment.

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Commercial electrodes need high mass loadings to realize superior energy and power densities. However, good electrochemical properties are usually achieved in the electrodes with ultrathin active materials (e.g., <1 mg cm−2). Good performance and high mass loading are often mutually exclusive characteristics. Herein, a unique 3D exfoliated carbon paper (EC) is demonstrated using a facile electrochemical method to support high mass loading MnO2 materials. The 3D‐interconnected graphene/graphite network, highly porous structure, as well as the strong interaction between the active materials and the substrate, allow efficient charge transport in the composite electrode, addressing the traditional limitations in high mass loading electrodes. The deposited MnO2 (mass loading: 9.5–10 mg cm−2) achieves a remarkable capacitive performance with high areal and gravimetric capacitances of 5.1 F cm−2 and 537 F g−1, respectively. A Zn–MnO2 battery is also assembled using MnO2/EC as the cathode. An excellent specific capacity of 368 mAh g−1 is also delivered. This MnO2/EC outperforms most of the reported MnO2‐based electrodes with similar loadings for capacitive and Zn‐ion battery applications, highlighting the great application potential of the 3D carbon paper support in electrochemical energy storage.

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