Reunderstanding aqueous Zn electrochemistry from interfacial specific adsorption of solvation structures

Abstract

Although sulfate- and sulfonate-based electrolytes have been widely used in the study on aqueous zinc-ion batteries (AZIBs), the discrepancies in the Faradaic reaction kinetics of cations interfacial chemistry including Mn2+...

Crowding Effect-Induced Zinc-Enriched/Water-Lean Polymer Interfacial Layer Toward Practical Zn-Iodine Batteries

“…By measuring the pressure difference and the streaming potential, the zeta potential of bare Zn (−8.195 mV) and Zn-CCS (−2.763 mV) could be calculated by Helmholtz–Smoluchowski formula as eq : ζ = 4 π η ε · UX Δ P · G where ζ is the zeta potential (V), η the viscosity of the medium (Pa s), ε the dielectric constant (F m –1 ), U the streaming potential (V), X the conductivity (A V m –1 ), Δ P the pressure difference (Pa), and G the correction factor. Lower potentials indicated that the charge distribution at the Zn-CCS interface was changed and the adsorption of anions was significantly weakened in the same environment. , Besides, Zn-CCS was rich in hydrophilic functional groups and had a network-like surface with a high specific surface area, which made it have good wettability to aqueous electrolytes than bare Zn (89°) and was beneficial for the Zn ion diffusion (Figure i) . Among this, the surface morphology becomes flat from unevenness as the electrodeposition time grows with the continuous generation of Zn-CCS, and thus, the apparent contact angle continues to increase (30 s–37°, 60 s–44°, 90s-50°, 120s-52°, 150s-68°, 180s-73°).…”

“…Lower potentials indicated that the charge distribution at the Zn-CCS interface was changed and the adsorption of anions was significantly weakened in the same environment. 30,31 Besides, Zn-CCS was rich in hydrophilic functional groups and had a network-like surface with a high specific surface area, which made it have good wettability to aqueous electrolytes than bare Zn (89°) and was beneficial for the Zn ion diffusion (Figure 2i). 32 Among this, the surface morphology becomes flat from unevenness as the electrodeposition time grows with the continuous generation of Zn-CCS, and thus, the apparent contact angle continues to increase (30 s−37°, 60 s−44°, 90s-50°, 120s-52°, 150s-68°, 180s-73°).…”

Achieving a dendrite-free Zn anode at high current densities via in situ polymeric interface design

“…Therefore, the protection of the Zn anode has received increasing attention to improve the overall performance of the aqueous Zn 2+ batteries. 19–21…”

One-Step Coprecipitation Synthesis of Titanium Hexacyanoferrate Nanosheet-Assembled Hierarchical Nanoflowers for Aqueous Zinc-Ion Batteries

“…Aqueous zinc-ion batteries (AZIBs) have gained increasing attention owing to their low redox potential (−0.76 V vs standard hydrogen electrode) and promising theoretical specific capacity (820 mA h g –1 ) with low cost and high safety. − However, the strong electrostatic interaction between the bivalent zinc ion and intercalation material seriously obstructs the development of cathode materials . As host materials for just commercialized sodium-ion batteries (SIBs), − Prussian blue analogues (PBAs) have also been recognized as one of the most prospective cathode materials for AZIBs − not only due to their unique 3D open framework structure and large interstitial sites capable of hosting alien Zn 2+ but also owing to their high working voltage, rich redox-active sites, low cost, and environmental friendliness. − The most representative PBAs are metal hexacyanoferrate (M a HCF) with a general formula of A x M a [Fe(CN) 6 ] y □ 1– y ·nH 2 O, where A, M a , and □ denote removable cations (Li + , Na + , K + , Zn 2+ , etc.…”