Sluggish CO 2 reduction/evolution kinetics at cathodes seriously impede the realistic applications of Li-CO 2 batteries. Herein, synergistic photoelectric effect and plasmonic interaction are introduced to accelerate CO 2 reduction/evolution reactions by designing a silver nanoparticle-decorated titanium dioxide nanotube array cathode. The incident light excites energetic photoelectrons/holes in titanium dioxide to overcome reaction barriers, and induces the intensified electric field around silver nanoparticles to enable effective separation/transfer of photogenerated carriers and a thermodynamically favorable reaction pathway. The resulting Li-CO 2 battery demonstrates ultra-low charge voltage of 2.86 V at 0.10 mA cm À 2 , good cycling stability with 86.9 % round-trip efficiency after 100 cycles, and high rate capability at 2.0 mA cm À 2 . This work offers guidance on rational cathode design for advanced Li-CO 2 batteries and beyond.

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Fiber solar cells have attracted significant interest as a promising wearable power supply solution for their merits of high flexibility, lightweight, and good compatibility with textile configuration and weaving process. However, because of the limited ion diffusion and charge transfer in the fiber counter electrode, the poor photovoltaic performances have long been one obstacle to hinder their real applications. Herein, in mimicking the efficient mass transport and exchange through the vascular tissue of plants like pine needle, a hierarchically assembled carbon nanotube (HCNT) fiber counter electrode is fabricated by a scalable process. The designed hierarchically aligned channels with large sizes of micrometers and small sizes of tens of nanometers in the HCNT fiber offers high‐flux pathways for rapid ion diffusion and abundant active area for charge transport, thus endowing the fiber dye‐sensitized solar cell with a record power conversion efficiency of 11.94%. By weaving such fiber solar cells in a scalable way, a flexible and breathable large photovoltaic textile (17 cm × 22 cm) is made to present a power output of 22.7 mW. These fiber solar cells are further integrated with fiber lithium‐ion batteries to efficiently power wearable electronics.

Photovoltaic devices represent an efficient electricity generation mode. Integrating them into textiles offers exciting opportunities for smart electronic textiles—with the ultimate goal of supplying power for wearable technology—which is poised to change how we design electronic devices. Many human activities occur indoors, so realizing indoor photovoltaic fibers (IPVFs) that can be woven into textiles to power wearables is critical, although currently unavailable. Here, we constructed a dye‐sensitized IPVF by incorporating titanium dioxide nanoparticles into aligned nanotubes to produce close contact and stable interfaces among active layers on a curved fiber substrate, thus presenting efficient charge transport and low charge recombination in the photoanode. With the combination of highly conductive core‐sheath Ti/carbon nanotube fiber as a counter electrode, the IPVF shows a certified power conversion efficiency (PCE) of 25.53% under 1500 lux illuminance. Its performance variation is below 5% after bending, twisting, or pressing for 1,000 cycles. These IPVFs were further integrated with fiber batteries as self‐charging power textiles, which were demonstrated to effectively supply electricity for wearables, solving the power supply problem in this important direction.This article is protected by copyright. All rights reserved

Sluggish CO 2 reduction/evolution kinetics at cathodes seriously impede the realistic applications of Li-CO 2 batteries. Herein, synergistic photoelectric effect and plasmonic interaction are introduced to accelerate CO 2 reduction/evolution reactions by designing a silver nanoparticle-decorated titanium dioxide nanotube array cathode. The incident light excites energetic photoelectrons/holes in titanium dioxide to overcome reaction barriers, and induces the intensified electric field around silver nanoparticles to enable effective separation/transfer of photogenerated carriers and a thermodynamically favorable reaction pathway. The resulting Li-CO 2 battery demonstrates ultra-low charge voltage of 2.86 V at 0.10 mA cm À 2 , good cycling stability with 86.9 % round-trip efficiency after 100 cycles, and high rate capability at 2.0 mA cm À 2 . This work offers guidance on rational cathode design for advanced Li-CO 2 batteries and beyond.