A new approach is employed to boost the electrochemical kinetics and stability of vanadium oxygen hydrate (VOH, V2O5·nH2O) employed for aqueous zinc-ion battery (ZIB) cathodes. The methodology is based on electrically conductive polyaniline (PANI) intercalated–exfoliated VOH, achieved by preintercalation of an aniline monomer and its in situ polymerization within the oxide interlayers. The resulting graphene-like PANI–VOH nanosheets possess a greatly boosted reaction-controlled contribution to the total charge storage capacity, resulting in more material undergoing the reversible V5+ to V3+ redox reaction. The PANI–VOH electrode obtains an impressive capacity of 323 mAh g–1 at 1 A g–1, and state-of-the-art cycling stability at 80% capacity retention after 800 cycles. Because of the facile redox kinetics, the PANI–VOH ZIB obtains uniquely promising specific energy–specific power combinations: an energy of 216 Wh kg–1 is achieved at 252 W kg–1, while 150 Wh kg–1 is achieved at 3900 W kg–1. Electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) analyses indicate that with PANI–VOH nanosheets, there is a simultaneous decrease in the charge transfer resistance and a boost in the diffusion coefficient of Zn2+ (by a factor of 10–100) vs the VOH baseline. The strategy of employing PANI for combined intercalation–exfoliation may provide a broadly applicable approach for improving the performance in a range of oxide-based energy storage materials.

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A stable lean‐electrolyte operating lithium–sulfur (Li–S) battery based on a cathode of Li2S in situ electrocatalytically deposited from L2S8 catholyte onto a support of metallic molybdenum disulfide (1T‐MoS2) on carbon cloth (CC) is created. The 1T‐MoS2 significantly accelerates the conversion Li2S8 catholyte to Li2S, chemically adsorbs lithium polysulfide (LiPSs) from solution, and suppresses crossover of the LiPSs to the anode. These experimental findings are explained by density functional theory calculations that show that 1T‐MoS2 gives rise to strong adsorption of polysulfides on its surface and is electrocatalytic for the targeted reversible Li–S conversion reactions. The CC/1T‐MoS2 electrode in a Li–S battery delivers an initial capacity of 1238 mAh g−1, with a low capacity fade of only 0.051% per cycle over 500 cycles at 0.5 C. Even at a high sulfur loading (4.4 mg cm−2) and low electrolyte/S (E/S) ratio of 3.7 µL mg−1, the battery achieves an initial reversible capacity of 1176 mA h g−1 at 0.5 C, with 87% capacity retention after 160 cycles. The post 500 cycles Li metal opposing 1T‐MoS2 is substantially smoother than the Li opposing CC, with XPS supporting the role of 1T‐MoS2 in inhibiting LiPSs crossover.

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Layered tin monosulfide (SnS) is a promising anode material for sodium-ion batteries because of its high theoretical capacity of 1020 mA h g–1. Its large interlayer spacing permits fast sodium-ion transport, making it a viable candidate for sodium-ion capacitors (SICs). In this work, we designed and synthesized oriented SnS nanosheets confined in graphene in the presence of poly­(diallyl dimethyl ammonium chloride) by electrostatic self-assembly during hydrothermal growth. SnS nanosheets growing along (l00) and (0l0) directions are suppressed because of the confinement by graphene, which exhibit smaller thickness and particle size. These nanostructures expose abundant open edges because of the presence of Sn4+–O, which offers rich active sites and Na+ easy transport pathways. Vacancies formed at these edges along with S and N codopants in the graphitic structure synergistically promoted Na+ surface adsorption/desorption. Such nanocomposites with SnS nanosheets confined by N,S codoped graphene demonstrated significantly enhanced pseudocapacitance. The SICs delivered excellent energy densities of 113 and 54 W h kg–1 at power densities of 101 and 11 100 W kg–1, respectively, with 76% capacity retention after 2000 cycles at 1 A g–1.