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One dimensional core/shell nanostructures consisting of two different semiconductors with appropriate band alignment are promising for photocatalytic hydrogen production due to their efficient light harvesting and fast carrier transport. In this work, CdS/ZnO core/shell nanofibers were successfully synthesized by one-pot single-spinneret electrospinning. The ZnO layered structures (60 nm in thickness) were uniformly grown onto continuous CdS core fibers (220 nm in diameter and several micrometers in length). The as-fabricated CdS/ZnO core/shell nanofibers as nanoheterojunction photocatalysts exhibited excellent visible light photocatalytic activity and stability for hydrogen production. The possible formation mechanism of the CdS/ZnO core/shell nanofibers was also proposed based on the experimental observations. Moreover, the morphologies and components of the as-prepared nanofibers can be controlled easily by tuning the annealing temperature and Zn/Cd ratios of the precursor solution.

Flexible metallic cobalt decorated CNT-grafted multichannel carbon fibers, co-doped with nitrogen and sulfur, exhibit excellent ORR and OER activities.

Lithium–sulfur batteries are appealing as high‐energy storage systems and hold great application prospects in wearable and portable electronics. However, severe shuttle effects, low sulfur conductivity, and especially poor electrode mechanical flexibility restrict sulfur utilization and loading for practical applications. Herein, high‐flux, flexible, electrospun fibrous membranes are developed, which succeed in integrating three functional units (cathode, interlayer, and separator) into an efficient composite. This structure helps to eliminate negative interface effects, and effectively drives synergistic boosts to polysulfide confinement, electron transfer, and lithium‐ion diffusion. It delivers a high initial capacity of 1501 mA h g−1 and a discharge capacity of 933 mA h g−1 after 400 cycles, with slow capacity attenuation (0.069% per cycle). Even under high sulfur loading (13.2 mg cm−2, electrolyte/sulfur ratio = 6 mL g−1) or in an alternative folded state, this three‐in‐one membrane still exhibits high areal capacity (11.4 mA h cm−2) and exceptional application performance (powering an array of over 30 light‐emitting diodes (LEDs)), highlighting its huge potential in high‐energy flexible devices.

Flexible power sources and efficient energy storage devices with high energy density are highly desired to power a future sustainable community. Theoretically, rechargeable metal−air batteries are promising candidates for the next-generation power sources. The rational design of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts with high catalytic activity is critical to the development of efficient and durable metal−air batteries. Herein, we propose a novel strategy to mass synthesize nonprecious transition-metal-based nitrogen/oxygen codoped carbon nanotubes (CNTs) grown on carbon-nanofiber films (MNO-CNT-CNFFs, M = Fe, Co, Ni) via a facile free-surface electrospinning technique followed by in situ growth carbonization. With a combination of the high catalytic activity of Fe-catalyzed CNTs and the efficient mass-transport characteristics of 3D carbon fiber films, the resultant flexible and robust FeNO-CNT-CNFFs exhibit the highest bifunctional oxygen catalytic activities in terms of a positive half-wave potential (0.87 V) for ORR and low overpotential (430 mV @ 10 mA cm −2 ) for OER. As proof-of-concept, newly designed hybrid Li−air batteries fabricated with FeNO-CNT-CNFFs as air electrode present high voltage (∼3.4 V), low overpotential (0.15 V), and long cycle life (over 120 h) in practical open-air tests, demonstrating the superiority of the freestanding catalysts and their promising potential for the applications in fuel cells and flexible energy storage devices.

N-doped TiO2 with a three-dimensionally ordered macroporous structure was fabricated by a one-step colloidal crystal-template method, which showed excellent photocatalytic activity under visible-light irradiation.

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