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In this work, the best operating parameters of NiO electrodeposition process have been identified using artificial intelligence and metaheuristics. The objective is maximizing of specific capacity of G-NiO electrodes for usage in electrochemical energy storage devices. The proposed strategy integrates ANFIS modelling and marine predators optimization (MPA). The study focuses on three operation parameters: deposition potential and time of the G-NiO and the concentration of the electrolyte, to maximize the specific capacity of G-NiO. Based on measured data, ANFIS model is created to simulate the electrodeposition process. Next, using MPA, the best values of deposition potential and time of the G-NiO and the concentration of the electrolyte are estimated. To confirm the advantage of the adopted strategy, the response surface methodology was utilized to check the findings. The integration between ANFIS and MPA succeeded in improving the specific capacity of G-NiO electrode by 12.7% compared to the response surface methodology.

Abstract Rechargeable aqueous zinc ion hybrid capacitors (ZIHCs), as an up‐and‐comer aqueous electrochemical energy storage system, endure in their infancy because of the substandard reversibility of Zn anodes, structural deterioration of cathode materials, and narrow electrochemical stability window. Herein, a scalable approach is described that addresses Zn‐anode/electrolyte interface and cathode materials associated deficiencies and boosts the electrochemical properties of ZIHCs. The Zn‐anode/electrolyte interface is self‐regulated by alteration of the traditional Zn2+ electrolyte with Na‐based supporting salt without surrendering the cost, safety, and green features of the Zn‐based system which further validates the excellent reversibility over 1100 h with suppressed hydrogen evolution. The deficits of cathode materials were overcome by using a high‐mass loaded, oxygen‐rich, 3D, multiscaled graphene‐like carbon (3D MGC) cathode. Due to the multiscaled texture, high electronic conductivity, and oxygen‐rich functional groups of 3D MGC, reversible redox capacitance was obtained with a traditional adsorption/desorption mechanism. Prototype ZIHCs containing the modified electrolyte and an oxygen‐rich 3D MGC cathode resulted in battery‐like specific energy (203 Wh kg−1 at 1.6 A g−1) and supercapacitor‐type power capability (4.9 kW kg−1 at 8 A g−1) with outstanding cycling durability (96.75% retention over 30 000 cycles at 10 A g−1). These findings pave the way toward the utilization of highly efficient ZIHCs for practical applications.

Graphene is fundamentally a two-dimensional material with extraordinary optical, thermal, mechanical, and electrical characteristics. It has a versatile surface chemistry and large surface area. It is a carbon nanomaterial, which comprises sp2 hybridized carbon atoms placed in a hexagonal lattice with one-atom thickness, giving it a two-dimensional structure. A large number of synthesis techniques including epitaxial growth, liquid phase exfoliation, electrochemical exfoliation, mechanical exfoliation, and chemical vapor deposition are used for the synthesis of graphene. Graphene prepared using different techniques can have a number of benefits and deficiencies depending on its application. This study provides a summary of graphene preparation techniques and critically assesses the use of graphene, its derivates, and composites in environmental applications. These applications include the use of graphene as membrane material for the detoxication and purification of water, active material for gas sensing, heavy metal ions detection, and CO2 conversion. Furthermore, a trend analysis of both synthesis techniques and environmental applications of graphene has been performed by extracting and analyzing Scopus data from the past ten years. Finally, conclusions and outlook are provided to address the residual challenges related to the synthesis of the material and its use for environmental applications.

Two-dimensional (2D) layered materials and their heterostructures have opened a new avenue for next-generation spintronic applications, benefited by their unique electronic properties and high crystallinity with an atomically flat surface. Here, we report magnetoresistance of vertical magnetic spin-valve devices with multi-layer (ML) MoSe2 and its heterostructures with few-layer graphene (FLG). We employed a micro-fabrication procedure to form ultraclean ferromagnetic–non-magnetic–ferromagnetic interfaces to elucidate the intrinsic spin-transferring mechanism through both an individual material and combinations of 2D layered materials. However, it is revealed that the polarity of tunneling magnetoresistance (TMR) is independent of non-magnetic spacers whether the spin valve is composed of a single material or a hybrid structure, but it strongly depends on the interfaces between ferromagnetics (FMs) and 2D materials. We observed positive spin polarizations in ML-MoSe2 and FLG/ML-MoSe2/FLG tunnel junctions, whereas spin-valve devices comprised of FLG/ML-MoSe2 showed a reversed spin polarization and demonstrated a negative TMR. Importantly, in Co/FLG/ML-MoSe2/FLG/NiFe devices, the polarization of spin carriers in the FM/FLG interface remained conserved during tunneling through MoSe2 flakes in spin-transferring events, which is understandable by Julliere’s model. In addition, large TMR values are investigated at low temperatures, whereas at high temperatures, the TMR ratios are deteriorated. Furthermore, the large values of driving ac-current also quenched the amplitude of TMR signals. Therefore, our observations suggest that the microscopic spin-transferring mechanism between ferromagnetic metals and 2D materials played a momentous role in spin-transferring phenomena in vertical magnetic spin-valve junctions.