Jasmin Shamshoddin Shaikh

This work reports an efficient method for facile synthesis of hierarchically porous carbon (WB‐AC) utilizing wheat bran waste. Obtained carbon showed 2.47 mmol g⁻¹ CO₂ capture capacity with good CO₂/N₂ selectivity and 27.35 to 29.90 kJ mol⁻¹ isosteric heat of adsorption. Rapid removal of MO dye was observed with a capacity of ~555 mg g⁻¹. Moreover, WB‐AC demonstrated a good OER activity with 0.35 V low overpotential at 5 mA cm⁻² and a Tafel slope of 115 mV dec⁻¹. It also exhibited high electrocatalytic HER activity with 57 mV overpotential at 10 mA cm⁻² and a Tafel slope of 82.6 mV dec⁻¹. The large SSA (757 m² g⁻¹) and total pore volume (0.3696 cm³ g⁻¹) result from N₂ activation contributing to selective CO₂ uptake, high and rapid dye removal capacity and superior electrochemical activity (OER/HER), suggesting the use of WB‐AC as cost effective adsorbent and metal free electrocatalyst.

The integrated carbon capture and conversion (ICCC) is a promising catalytic process to produce syngas from CO₂ and CH₄ via a combined separation and reactor unit. Besides, its performance can fluctuate from the inconsistent feed ratio resulting from the flue gas unit. Herein, the Ratings concept based on density functional theory (DFT) is applied to overcome these problems in a two‐step protocol: (i) catalyst identification, which designates the catalyst characteristics and predicts performance based on reactivity (RT−R) and stability (RT−S) Ratings calculated based on activation energies obtained either from experiments or DFT, and (ii) catalyst optimization that optimized a catalyst's performance via the determination of new operating condition accounted for its deactivation over time. Moreover, temperature and feed ratio sensitivity were investigated, revealing that most catalysts are more sensitive to temperature change than the feed ratio.

In recent years, modern appliances require high energy density with a burst power supply. Hybrid supercapacitors show high performance based on high energy density without compromising power density and stability over thousands of charge–discharge cycles. In this work, the optimized hybrid electrodes using lanthanum-doped hematite (lanthanum-doped iron oxide) noted as 7.5%La-HMT as a negative electrode and hydrous cobalt phosphate (CoPO) as a battery-type positive electrode have been successfully fabricated via a simple hydrothermal method and a facile co-precipitation method, respectively. The 7.5%La-HMT showed excellent electrochemical performance due to doping of rare-earth La³⁺ metal ions, resulting in improvised active sites and reduction in the equivalent resistance. The 7.5%La-HMT operated at a high potential window (0 to −1.2 V) with an ultra-high specific capacitance (S_p) of 1226.7 F g⁻¹ at 1 A g⁻¹ with capacitance retention of 89.3% over 1000 cycles. CoPO could be operated at a high working window (0 to 0.45 V) with a specific capacity of 121.7 mA h g⁻¹ at a current density of 2 A g⁻¹ with capacitance retention of 85.4% over 1000 cycles. The configured CoPO//KOH//10%La-HMT aqueous hybrid capacitor device (Aq-HSC) could be operated at a potential window of 1.6 V and delivered a maximum energy density (E.D) of 83.6 W h kg⁻¹ at a power density (P.D) of 3.2 kW kg⁻¹ with S_p of 235.0 F g⁻¹ at 2 A g⁻¹ and 89.0% S_p retention over 5000 cycles. The simplicity of the synthesis methods for CoPO and 7.5%La-HMT along with their superior super-capacitive properties make them suitable for advanced electrical devices and hybrid vehicles.

The researchers across the globe are working on improvement in energy density of supercapacitor without compromising its inherent supercapacitive properties.^[1–4] The upgraded hybrid supercapacitor is derived from a battery type anode, a capacitive type cathode and organic electrolyte. However, the performance of hybrid supercapacitor is limited by the imbalance kinetics between the anode and cathode due to sluggish Faradic reaction of anode materials and less charge storage capacity of cathode materials. The design and development of lithium ion hybrid supercapacitor (LIC) can be possible by engineering anode, cathode and electrolyte materials. In this review, we focus on the evolution of anode materials for LICs fabrication. Different strategies to balance the kinetics between the cathode and the anode have already been reported, such as the engineering of novel materials and fabrication of different nanoarchitectures. LICs have been fabricated by tailoring different nanoarchitectures such as particles (0D), nanorods/nanowires/nanotubes (1D), thin sheets (2D) and hierarchical architectures (3D). The fabrication of nanostructured active materials with desired morphology (0D, 1D, 2D and 3D) and sizes with high aspect ratios facilitate fast lithium‐ion insertion and extraction. The anode materials are divided into three types (i) lithium insertion reaction mechanism (ii) conversion reaction mechanism (iii) and the alloying reaction mechanism. The lithium insertion reaction‐based materials have high stability whereas less capacity and energy density. In contrast to this, the conversion type electrodes have high energy density but low stability. Alloying type materials have ultra‐high energy density while very low stability and reversibility. Hence, for getting high performance LIC all above mentioned aspects are required to be considered.