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This article reports the first instance of exploring a chemically Zn(II) preinserted organic−inorganic hybrid material [vanadyl ethylene glycolate or VEG, (VO(CH 2 O) 2 )] as an efficient cathode for rechargeable zinc-ion batteries (ZIBs). The control VEG electrode synthesized by a glycothermal process showed a modest specific capacity of 157 mAh/g at 0.1 A/g current density, however, suffered from poor rate capability and cycle stability due to structural dissolution. Chemically Zn(II) preinsertion into VEG (Zn-VEG) catalyzed the Zn 2+ intercalation in the Zn-VEG cathode with a significantly decreased charge transfer resistance, resulting in high discharge capacity of 217 mAh/g (at 0.1 A/g) accompanied by excellent rate capability with ∼50% capacity retention on increasing the current by 50 times. A first-principles-based hybrid densityfunctional theory (DFT) study revealed that the electronic structure of the Zn-intercalated VEG is thermodynamically stable, indicating an energetically favorable Zn-ion intercalation process. The Zn(II) preinserted VEG cathode allowed faster ionic diffusion (D Zn 2+ in the order of 10 −9 cm 2 /s), and the diffusion controlled process was the major contributor (∼66.9%) to the overall capacity at low scan rate (0.1 mV/s) and remained significant (43.8%) even at high scan rate of 0.8 mV/s. Furthermore, the Zn(II) preinsertion in the VEG could act as a bridge to hold the VEG layers firmly. This provides the desired structural stability to the Zn-VEG cathode during a continuous Zn 2+ insertion/deinsertion process, resulting in excellent cycle stability with only ∼0.005% capacity loss per cycle over 2000 cycles (at 4 A/g) while maintaining a high columbic efficiency of 99.9% throughout the cycles. The high capacity accompanied by excellent rate capability and cycle stability supports the as-prepared Zn(II) preinserted organo-vanadyl hybrid electrode to be a potential cathode material for ZIBs.

Tendril-like functional carbon helices (TLFCHs) was successfully prepared directly from Parthenium hysterophorus using a solvothermal method employing a deep eutectic solvent as both soft template and catalyst. TLFCHs showed significant potential as a host for an enzyme without compromising the catalytic activity.

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