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Aqueous Zn‐Iodine (I2) batteries are attractive for large‐scale energy storage. However, drawbacks include, Zn dendrites, hydrogen evolution reaction (HER), corrosion and, cathode "shuttle" of polyiodines. Here we report a class of N‐containing heterocyclic compounds as organic pH buffers to obviate these. We evidence that addition of pyridine /imidazole regulates electrolyte pH, and inhibits HER and anode corrosion. In addition, pyridine and imidazole preferentially absorb on Zn metal, regulating non‐dendritic Zn plating /stripping, and achieving a high Coulombic efficiency of 99.6 % and long‐term cycling stability of 3200 h at 2 mA cm−2, 2 mAh cm−2. It is also confirmed that pyridine inhibits polyiodines shuttling and boosts conversion kinetics for I−/I2. As a result, the Zn‐I2 full battery exhibits long cycle stability of >25 000 cycles and high specific capacity of 105.5 mAh g−1 at 10 A g−1. We conclude organic pH buffer engineering is practical for dendrite‐free and shuttle‐free Zn‐I2 batteries. [ABSTRACT FROM AUTHOR]

Zinc metal battery (ZMB) is promising as the next generation of energy storage system, but challenges relating to dendrites and corrosion of the zinc anode are restricting its practical application. Here, to stabilize Zn anode, we report a controlled electrolytic method for a monolithic solid‐electrolyte interphase (SEI) via a high dipole moment solvent dimethyl methylphosphonate (DMMP). The DMMP‐based electrolytes can generate a homogeneous and robust phosphate SEI (Zn3(PO4)2 and ZnP2O6). Benefiting from the protecting impact of this in situ monolithic SEI, the zinc electrode exhibits long‐term cycling of 4700 h and a high Coulombic efficiency 99.89 % in Zn|Zn and Zn|Cu cell, respectively. The full V2O5|Zn battery with DMMP‐H2O hybrid electrolyte exhibits a high capacity retention of 82.2 % following 4000 cycles under 5 A g−1. The first success in constructing the monolithic phosphate SEI will open a new avenue in electrolyte design for highly reversible and stable Zn metal anodes. [ABSTRACT FROM AUTHOR]

Photocatalytic performance can be optimized via introduction of reactive sites. However, it is practically difficult to engineer these on specific photocatalyst surfaces, because of limited understanding of atomic‐level structure‐activity. Here we report a facile sonication‐assisted chemical reduction for specific facets regulation via oxygen deprivation on Bi‐based photocatalysts. The modified Bi2MoO6 nanosheets exhibit 61.5 and 12.4 μmol g−1 for CO and CH4 production respectively, ≈3 times greater than for pristine catalyst, together with excellent stability/reproducibility of ≈20 h. By combining advanced characterizations and simulation, we confirm the reaction mechanism on surface‐regulated photocatalysts, namely, induced defects on highly‐active surface accelerate charge separation/transfer and lower the energy barrier for surface CO2 adsorption/activation/reduction. Promisingly, this method appears generalizable to a wider range of materials. [ABSTRACT FROM AUTHOR]

Zinc‐based electrochemistry is attracting significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. However, the grid‐scale application is plagued by limited output voltage and inadequate energy density when compared with more conventional Li‐ion batteries. Herein, we propose a latent high‐voltage MnO2 electrolysis process in a conventional Zn‐ion battery, and report a new electrolytic Zn–MnO2 system, via enabled proton and electron dynamics, that maximizes the electrolysis process. Compared with other Zn‐based electrochemical devices, this new electrolytic Zn–MnO2 battery has a record‐high output voltage of 1.95 V and an imposing gravimetric capacity of about 570 mAh g−1, together with a record energy density of approximately 409 Wh kg−1 when both anode and cathode active materials are taken into consideration. The cost was conservatively estimated at