Self-assembled polyoxovanadate-intercalated layered double hydroxide nanosheets hybridized with graphene oxide for extrinsic supercapacitors

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024, Vol.12 (23), p.1391-13914
• Main Authors: Padalkar, Navnath S, Dubal, Deepak P, Park, Jong Pil
• Format: Article
• Language: English
• Subjects: Activated carbon; Capacitance; Charge transport; Chromium; Electrochemical analysis; Electrochemistry; Graphene; Hydroxides; Inorganic compounds; Nanosheets; Nickel; Optimization; Potassium hydroxides; Self-assembly; Specific energy; Supercapacitors
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta00794h

Hybrid materials integrate unique organic and inorganic compounds to create innovative materials that harness the optimal characteristics of each component, enhancing the electrochemical performance. Herein, a novel lattice engineering strategy has been established to synthesize self-assembled 2D nickel chromium layered double hydroxide (NC-LDH) nanosheets intercalated with 0D polyoxovanadate (POV) and hybridized with graphene oxide (GO) nanosheets (NCVG). The control of the POV/GO ratio is demonstrated to be crucial in optimizing the layer-by-layer-ordered porous stacking structure and the charge transport behavior, resulting in a remarkable increase in the cycling stability and rate performance of lattice-engineered NCVG nanoarchitecture as compared to NC-LDH. Later, a hybrid supercapacitor device was fabricated using NCVG as the cathode and activated carbon (AC) as the anode. The resulting device (NCVG-2//KOH//AC) delivered a specific energy of 73.8 W h kg −1 at a specific power of 1.06 kW kg −1 . The practical feasibility of the device in wearable applications was demonstrated by assembling a hybrid all-solid-state supercapacitor (NCVG-2//PVA-KOH//AC), which achieved an excellent capacitance retention of 92% over 12 000 cycles. This work provides a new opportunity to develop outstanding porous layer-by-layer assembled architectures for the development of efficient materials for energy-oriented applications. POV intercalated LDH hybridized with GO increases basal spacing, forming a porous structure and improving conductivity. This nanoarchitecture, with expanded surface area and abundant redox sites, provides exceptional electrochemical activity.