Anant Prakash Pandey

Rechargeable Iron‐ion batteries (IIBs) are emerging as a sustainable alternative to conventional rechargeable batteries; however, their cathode development is hindered by sluggish Fe‐ion diffusion, limited conductivity, and interfacial instability. Addressing these challenges requires designing cathode materials with high conductivity, large surface area, and stable electrochemical interfaces. This work explores carbon aerogel (CA)‐based cathodes to overcome these limitations and enhance Fe‐ion storage performance. Highly porous CA, used as the cathode material, is synthesized using the sol–gel process and confirmed using transmission electron microscopy, field emission scanning electron microscopy, X‐ray diffraction, and Brunauer–Emmett‐Teller measurements. Detailed cyclic voltammetry is investigated at different scan rates to understand the characteristics of the Fe‐ion storage in CA hosts during cycling. The galvanostatic charging–discharging (GCD) is determined at various current densities, showing a high discharge capacity of ≈150 mAh g ⁻¹ and ≈45 mAh g ⁻¹ at 35 mA g ⁻¹ and 1000 mA g ⁻¹ discharge current densities, respectively. The capacity retention is more than ≈60%, with more than 85% Coulombic efficiency (CE) after 750 cycles at 1000 mA g ⁻¹ , and fast charge–discharge characteristics of ≈18C rate. The galvanostatic intermittent titration technique (GITT) measurements are also performed to check the diffusion characteristics of the Fe‐ion during charging and discharging. A digital clock and 5V light‐emitting diode are connected to CA‐based Fe‐ion coin cells to demonstrate the potential of IIBs. A detailed electrochemical impedance spectroscopy and postmortem measurements before and after the GCD cycling suggest a slight degradation of electrochemical performance, which is attributed to the oxidation of the anode during cycling.

Rechargeable iron-ion batteries (RIIBs) are considered one of the alternatives to lithium-ion batteries (LIBs) owing to their high volumetric energy density and low-cost fabrication under ambient conditions. A crucial aspect of RIIBs lies in developing high-performance cathode materials with high cycling stability and fast charge–discharge characteristics. We developed highly stable iron oxide microspheres (Fe₃O₄-MS) via solvothermal synthesis. Various electrochemical measurements were performed, including cyclic voltammetry (CV) to understand the redox mechanism and diffusion characteristics of iron-ions, galvanostatic charging discharging (GCD) for cycling stability analysis, and electrochemical impedance spectroscopy (EIS) for different electrode resistance analyses. RIIBs exhibit a high specific capacity of 155 mA h g⁻¹ at 25 mA g⁻¹ and 60 mA h g⁻¹ at a higher current density of 500 mA g⁻¹ (∼8C), with 92% retention capacity and fast charge–discharge characteristics. Electronically powered gadgets were used to demonstrate the practical utility of RIIBs. The remarkable electrochemical performance observed due to highly stable Fe₃O₄-MS is confirmed by ex situ characterization after the complete cycling of the cell compared to pristine electrodes, and these results strongly correlated with impedance analysis. Thus, the present work facilitates the development of an efficient cathode material for RIIBs.

One of the greatest alternatives to Li‐ion batteries is an Al‐air battery as it is more economically feasible and less toxic together with relatively better electrochemical performance. The design of the cell and the selection of electrode for improved electrochemical performance are the primary factors influencing the performance of the Al‐air battery. The present study focuses on designing an efficient air cathode host to lengthen the battery's lifespan using highly porous carbon aerogel. Initially, the carbon aerogel (CA) material is synthesized using sol‐gel polymerization process and characterized using XRD, RAMAN, SEM, and BET. The synthesized CA is used to fabricate the electrode stacking using the in‐house‐built Al‐air cell. The performance of carbon aerogel coated on carbon cloth as air cathode has been evaluated using a galvanostatic discharge of the assembly at different current rates, and the specific capacity is recorded. The highest specific capacity observed is ~683 mAh g⁻¹ at 2.551 mA cm⁻² current density. The acquired results demonstrate the superiority of the present electrodes material compared to currently used air electrode. The improved electrochemical stability and the robust pore network in CA allow oxygen to pass through the cathode end for chemical reaction. Overall, this enhances kinetics and makes the interactions between oxygen and aluminum easier to generate higher current.

One of the greatest alternatives to Li-ion batteries is an Al-air battery. The aluminium (Al) is more effective as a battery because of its viability and nontoxicity. The design of cell and electrode stacking affect the performance of Al-air battery. The present study focuses on designing an efficient air cathode host to lengthen the battery’s lifespan using highly porous carbon aerogel. Initially, the carbon aerogel (CA) material is synthesized using sol-gel polymerization process and characterized using XRD, SEM, and BET. The synthesized CA is used to fabricate the electrode stacking using the in-house-built Al-air cell. The performance of carbon aerogel coated on carbon cloth as air cathode has been evaluated using a galvanostatic discharge of the assembly at different current rates, and the specific capacity is recorded. The highest specific capacity observed is ~ 683 mAh g-1 at 2.551 mA cm ^-2 current density. The acquired results demonstrate the superiority of the present electrodes material compared to currently used air electrode. The improved electrochemical stability and the robust pore network in CA allow oxygen to pass through the cathode end for chemical reaction. Overall, this enhances kinetics and makes the interactions between oxygen and aluminum to generate higher current because of relatively faster chemical reaction.