Multifunctionality of Partially Reduced Graphene Oxide–CrVO₄Nanocomposite: Electrochemical and Photocatalytic Studies with Theoretical Insight from Density Functional Theory

Abstract

The CrVO4 and reduced graphene oxide (rGO)–CrVO4 composite has been synthesized through solid-state reaction and modified Hummer method and ultrasonication-assisted solid-state reaction method, respectively. The structural, compositional, and morphological features were studied by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques. The Raman spectroscopy shows the indicative GO, and CrVO4 peaks, respectively, and the coexistence of these peaks in composite material. The photocatalytic activity of rGO–CrVO4 composite evaluated by photocatalytic degradation of methylene blue dye under UV-light irradiation shows improved ability for composite as compared to the parent compound CrVO4. The rate constant evaluated for rGO–CrVO4 is 6.7 × 10–2 min–1. Electrochemical characterization through cyclic voltammetry, galvanostatic charging and discharging, and impedance analysis was carried out. The rGO–CrVO4 composite exhibits a higher specific capacitance, 102.66 F/g @ current density of 0.5 mA/cm2, as compared to the parent CrVO4, 30.87 F/g @ current density of 0.5 mA/cm2. We have also performed extensive density functional theory simulations to qualitatively support our experimental findings by presenting the quantum capacitance and providing the insight from electronic density of states for enhanced capacitance for rGO–CrVO4 nanocomposite. Presence of additional C 2p states from rGO results enhanced the density of states which is responsible for improved supercapacitance performance of rGO–CrVO4 compared to bare CrVO4. These encouraging results illustrate the exciting potential for-high performance applications for GO composites with multifunctionality for multiple applications.

High pressure crystal structures of orthovanadates and their properties

“…and in electrochemical applications [98]. FeVO4 has a rich polymorphism with several crystal structures reported in the literature [99].…”

Sucrose-assisted rapid synthesis of multifunctional CrVO4 nanoparticles: a new high-performance cathode material for lithium ion batteries

“…The resulting good crystalline CrVO 4 at a small size is may be due to the carbonization of sucrose and liberation of gas products during thermal treatment [22]. Thus, the proposed synthesis protocol yields pure and multifunctional CrVO 4 nanoparticles in a shorter time compared with the previously reported methods [11,18].…”

“…CrVO 4 has extensively been used in catalysis and photocatalysis [10], supercapacitor [11], superprotonic conductors [12], high-power lasers [13], potentiometric sensors [14], scintillators [15], and gas sensors [16]. In the present paper, multifunctional CrVO 4 is being introduced as a new and novel cathode material for lithium ion battery.…”

“…Previously, many synthetic protocols have been employed for the synthesis of CrVO 4 . The reported synthesis protocols use very long heating time to achieve pure phase of CrVO 4 , and this long heating time leads to the agglomeration of crystallites and thereby leads to bulk CrVO 4 particles, which significantly limit the electrochemical performance [11,18].…”

Metallic porous nitride single crystals at two-centimeter scale delivering enhanced pseudocapacitance

“…Transition-metal nitrides with unsaturated nitrogen coordination are generally a kind of electronic conductors. The nearest neighboring metal ions with short distances would provide a possibility of formation of metallic bond that facilitates electron transport in the connected pathway 4–9 . Coordinatively unsaturated metal-nitrogen active sites on electrode surfaces normally offer the ability to host redox reactions that give rise to reversible energy storage in the form of pseudocapacitance.…”