As the global water shortage becomes increasingly serious, it is highly imperative to develop efficient, renewable, and large-scale water purification devices. Herein, an efficient solar-driven water purification device of wood coated with Fe2O3 nanoparticle-decorated carbon nanotubes (Fe2O3/CNT) is fabricated in only a few seconds by one-step combustion of ferric acetylacetonate in an ambient environment. The thin layer of the Fe2O3/CNT hybrid coated on the upper surface of the wood serves as a solar-light absorber for converting solar energy to thermal energy, while the thermally insulating wood layer with vertically aligned channels endows the device with rapid water upward transport and localizes the generated heat inside the Fe2O3/CNT layer for solar-driven water evaporation. As a result, the wood/Fe2O3/CNT device achieves a high water steam generation capability of 1.42 kg m–2 h–1 along with an excellent evaporation efficiency of 87.2% under 1 sun irradiation, higher than most of the wood-based solar-driven water evaporation device reported. This device is also efficient in the purification of seawaters and wastewaters. This work demonstrates a rapid and facile methodology for large-scale fabrication of wood/Fe2O3/CNT devices for efficient solar-driven water purification.

Although supercapacitors attract tremendous attention due to their high power density, long cycle life, and high efficiency, it is still a challenge to prepare flexible and wearable supercapacitors with stable electrochemical performances during bending, twisting, and stretching. Herein, a vertically aligned and physically cross-linked poly­(vinyl alcohol)–H2SO4 hydrogel (APH) film is fabricated by freezing–thawing and directional-freezing approaches, and polyaniline (PANI) is subsequently grown in situ on both sides of the APH film to generate a flexible and conductive APH–PANI film with vertically aligned channels as both polymeric electrodes and electrolyte of an integrated supercapacitor. The APH–PANI supercapacitor exhibits an outstanding specific capacitance of 25.86 mF cm–2 at a current density of 0.05 mA cm–2, 4.65 times its counterpart with a random network, because of the rapid transport of ions within the aligned channels between the two electrodes, which remains at 94% after 2000 charge/discharge cycles. More importantly, the APH–PANI supercapacitor not only presents excellent flexibility and stable electrochemical performances during twisting, bending, and stretching but also exhibits a superior self-healable capability by reorganizing dynamic hydrogen bonding. Thanks to the unique structure, high performance, and mechanical stability, the integrated APH–PANI supercapacitor shows a great potential for high-performance flexible devices.

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Although wood-derived carbon (WC) and its derivatives are promising electrodes for supercapacitors because of their hierarchically porous architecture, superior mechanical flexibility, and environmental friendliness, pure WC electrodes usually exhibit poor...