A Co@N-CNTF electrocatalyst derived from a metal–organic framework exhibits high catalytic activity in the ORR, OER and HER.

Hybrid capacitors exhibit promise to bridge the gap between rechargeable high-energy density batteries and high-power density supercapacitors. This separation is due to sluggish ion/electron diffusion and inferior structural stability of battery-type materials. Here, a topochemistry-driven method for constructing expanded 2D rhenium selenide intercalated by nitrogen-doped carbon hybrid (E-ReSe 2 @INC) with a strong-coupled interface and weak van der Waals forces, is proposed. X-ray absorption spectroscopy analysis dynamically tracks the transformation from ReO into ReC bonds. The bridging bonds act as electron transport channels to enable improved conductivity and accelerated reaction kinetics. The expanded interlayer-spacing of ReSe 2 layer by INC facilitates ion diffusion and ensures structural stability. As expected, the E-ReSe 2 @INC achieves an improved rate capability (252.5 mAh g −1 at 20 A g −1 ) and long-term cyclability (89.6% over 3500 cycles). Moreover, theoretical simulations reveal the favorable Na + storage kinetics can be ascribed to its low bonding energy of −0.06 eV and diffusion barrier of 0.08 eV for sodium ions. Additionally, it is demonstrated that 3D printed sodium-ion hybrid capacitors deliver high energies/power densities of 81.4 Wh kg −1 /0.32 mWh cm −2 and 9992.1 W kg −1 /38.76 mW cm −2 , as well as applicability in a wide temperature range.

The development of aqueous rechargeable zinc-iodine (Zn-I 2 ) batteries is still plagued by the polyiodide shuttle issue, which frequently causes batteries to have inadequate cycle lifetimes. In this study, quaternization engineering based on the concept of "electric double layer" is developed on a commercial acrylic fiber skeleton ($1.55-1.7 kg −1 ) to precisely constrain the polyiodide and enhance the cycling durability of Zn-I 2 batteries. Consequently, a high-rate (1 C-146.1 mAh g −1 , 10 C-133.8 mAh g −1 ) as well as, ultra-stable (2000 cycles at 20 C with 97.24% capacity retention) polymer-based Zn-I 2 battery is reported. These traits are derived from the strong electrostatic interaction generated by quaternization engineering, which significantly eliminates the polyiodide shuttle issue and simultaneously realizes peculiar solution-based iodine chemistry (I − /I 3 − ) in Zn-I 2 batteries. The quaternization strategy also presents high practicability, reliability, and extensibility in various complicated environments. In particular, cutting-edge Zn-I 2 batteries based on the concept of derivative material (commercially available quaternized resin) demonstrate ≈100% capacity retention over 17 000 cycles at 20 C. This work provides a general and fresh insight into the design and development of large-scale, low-cost, and high-performance zinc-iodine batteries, as well as, other novel iodine storage systems.

Rechargeable aqueous zinc‐iodine batteries (ZIBs) are considered a promising newly‐developing energy‐storage system, but the corrosion and dendritic growth occurring on the anode seriously hinder their future application. Here, the corrosion mechanism of polyiodide is revealed in detail, showing that it can spontaneously react with zinc and cause rapid battery failure. To address this issue, a sulfonate‐rich ion‐exchange layer (SC‐PSS) is purposely constructed to modulate the transport and reaction chemistry of polyiodide and Zn2+ at the zinc/electrolyte interface. The resulting ZIBs can work properly over 6000 cycles with high‐capacity retention (90.2%) and reversibility (99.89%). Theoretical calculations and experimental characterization reveal that the SC‐PPS layer blocks polyiodide permeation through electrostatic repulsion, while facilitating desolvation of Zn(H2O)62+ and restricting undesirable 2D diffusion of Zn2+ by chemisorption.

Integration of nanostructured electrocatalysts into a 3D ordered assembly is beneficial for boosting their catalytic performance across various energy conversion applications. In this work, a self-templated carbonization strategy for synthesizing heterostructures of transition metal phosphide@nitrogen/phosphorus dual-doped carbon quasiaerogels (TMP@NPCA) is presented using a rationally designed precursor of a metallogel with Zn/M (M = Co, Fe, and Ni) bimetallic clusters (BMOG) and nitrogen/phosphorus chelate ligands. During the self-templated carbonization, the Zn ions among the BMOG boost a simultaneous catalytic carbonization and activation process of the resultant TMP@NPCA, whereas the M ions offer a versatile self-phosphating preparation of TMP nanoparticles (e.g., CoP, FeP, and Ni 2 P) within the TMP@NPCA. As a proof of concept, the TMP@NPCA catalysts deliver an excellent bifunctional catalytic activity and outstanding stability toward the oxygen reduction reaction and hydrogen evolution reaction, offering competitive advantages to achieve supreme bifunctional catalysis performance over the state-of-the-art TMP catalysts for renewable energy conversion systems.