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.

Coulomb-explosion velocity-map imaging is a new and potentially universal probe for gas-phase chemical dynamics studies, capable of yielding direct information on (time-evolving) molecular structure. The approach relies on a detailed understanding of the mapping between initial atomic positions within the molecular structure of interest and the final velocities of the fragments formed via Coulomb explosion. Comprehensive on-the-fly ab initio trajectory studies of the Coulomb explosion dynamics are presented for two prototypical small molecules, formyl chloride and cis-1,2dichloroethene, in order to explore conditions under which reliable structural information can be extracted from fragment velocity-map images. It is shown that, for low parent ion charge states, the mapping from initial atomic positions to final fragment velocities is complex, and very sensitive to the parent ion charge state as well as many other experimental and simulation parameters. For high charge states, however, the mapping is much more straightforward and dominated by Coulombic interactions (moderated, if appropriate, by the requirements of overall spin conservation). This study proposes minimum requirements for the high-charge regime, highlights the need to work in this regime in order to obtain robust structural information from fragment velocity-map images, and suggests how quantitative structural information may be extracted from experimental data.Several new and exciting experimental techniques for probing isolated (i.e. gas phase) molecules with high spatial and temporal resolution have recently been developed, and are now sufficiently mature to provide fundamental insights into phenomena such as the time evolving coupled electron and nuclear dynamics of molecules immediately following photoexcitation. Examples include timeresolved photoelectron spectroscopy, 1-5 X-ray scattering, 6 electron diffraction 7-9 and transient X-ray absorption spectroscopies. [10][11][12] Key to each of these developments have been advances in the availability and the ease of use of ultrafast laser sources delivering femtosecond (fs), and sub-fs 13 pulses across broad regions of the electromagnetic spectrum. These techniques all come with attendant challenges, however. Scattering and absorption methods require relatively high sample number or column densities, which limits the range of gas-phase systems amenable to study. Timeresolved photoelectron spectroscopy is much more sensitive: each molecule that is photoionized reports directly via the ejected electron. However, as with each of these new techniques, any full analysis of the measured data is heavily dependent on the availability of similarly cutting-edge theory, e.g. electronic structure calculations for the states involved in both the pump and the probe steps, and proper treatment of the excited state dynamics encompassing any non-adiabatic couplings en route to the ultimate products.Coulomb explosion imaging (CEI) -and its more recent variant Coulomb explosion velocity-map imaging (CE-VMI) -is an...

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The Coulomb explosion (CE) of jet-cooled CH 3 I molecules using ultrashort (40 fs), nonresonant 805 nm strongfield ionization at three peak intensities (260, 650, and 1300 TW cm −2 ) has been investigated by multimass velocity map imaging, revealing an array of discernible fragment ions, that is,, and H 3 + . Complementary ab initio trajectory calculations of the CE of CH 3 I Z+ cations with Z ≤ 14 identify a range of behaviors. The CE of parent cations with Z = 2 and 3 can be well-described using a diatomic-like representation (as found previously) but the CE dynamics of all higher CH 3 I Z+ cations require a multidimensional description. The ab initio predicted I q+ (q ≥ 3) fragment ion velocities are all at the high end of the velocity distributions measured for the corresponding I q+ products. These mismatches are proposed as providing some of the clearest insights yet into the roles of nonadiabatic effects (and intramolecular charge transfer) in the CE of highly charged molecular cations.