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Photovoltaics are an important source of renewable energy, but due to the intermittent nature of insolation, solar cells usually need to be connected to rechargeable batteries, electrochemical capacitors or other energy storage devices, which adds to the complexity and cost of these systems. In this work, a cathode design for photo‐rechargeable zinc‐ion batteries (photo‐ZIBs) is reported, that is inherently capable of harvesting sunlight to recharge without the need for external solar cells. The proposed photocathodes, comprising a composite of vanadium dioxide nanorods and reduced graphene oxide, are engineered to provide the necessary charge separation and storage for photocharging under illumination. The photo‐ZIBs achieve capacities of ≈282 mAh g−1 in the dark and ≈315 mAh g−1 under illumination, at 200 mA g−1, demonstrating the use of light not only to charge the devices, but additionally to enhance their capacity. The photo‐ZIBs also demonstrate enhanced high‐rate capabilities under illumination, as well as a capacity retention of ≈90% over 1000 cycles. The proposed photo‐ZIBs are considered a promising new technology for addressing energy poverty, due to their high performance and inherent cost‐efficiency and safety.

2D nanomaterials have been found to show surface‐dominant phenomena and understanding this behavior is crucial for establishing a relationship between a material's structure and its properties. Here, the transition of molybdenum disulfide (MoS2) from a diffusion‐controlled intercalation to an emergent surface redox capacitive behavior is demonstrated. The ultrafast pseudocapacitive behavior of MoS2 becomes more prominent when the layered MoS2 is downscaled into nanometric sheets and hybridized with reduced graphene oxide (RGO). This extrinsic behavior of the 2D hybrid is promoted by the fast Faradaic charge‐transfer kinetics at the interface. The heterostructure of the 2D hybrid, as observed via high‐angle annular dark field–scanning transmission electron microscopy and Raman mapping, with a 1T MoS2 phase at the interface and a 2H phase in the bulk is associated with the synergizing capacitive performance. This 1T phase is stabilized by the interactions with the RGO. These results provide fundamental insights into the surface effects of 2D hetero‐nanosheets on emergent electrochemical properties.

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Despite the significant impact of sodium (Na) storage systems in terms of natural abundance and environmental friendliness, high-performance pseudocapacitive mterials in organic electrolytes remain challenging. Here, we demonstrate the pseudocapacitive Na-ion storage of hierarchically structured, phosphorus-incorporating steam-activated nanoporous carbons (P-aCNs) with improved rate and cyclic capabilities in organic electrolytes. The P-aCNs with a hierarchical honeycomb structure are derived from lignocellulosic biomass via a proposed synthetic process. The prominent pseudocapacitive behaviors of the P-containing groups in organic Na-ion electrolytes are confirmed by the surface area-independent and surface-confined capacitances, distinctive redox waves, and strong binding with Na-ions. In particular, the P-aCN demonstrates the cyclic stability of 96.0% over 100 000 cycles in the full cell, achieving a high capacitance of 265.43 F g–1 and rate capability of 75%. These Na-ion pseudocapacitive features of P-aCNs arising from the hierarchical interconnected porosity and the redox-active P=O bonds are comprehensively investigated by experimental and computational analyses.