Mesoporous Nanohybrids of 2D Ni‐Cr‐Layered Double Hydroxide Nanosheets Pillared with Polyoxovanadate Anions for High‐Performance Hybrid Supercapacitor
Navnath S. Padalkar, Shrikant V. Sadavar, Rohini B. Shinde, A. S. Patil, Umakant M. Patil, Dattatray S. Dhawale, Habib M. Pathan, Shrikrishna D. Sartale, Vinayak G. Parale, Ajayan Vinu, C.D. Lokhande, Jayavant L. Gunjakar
Abstract
Abstract In this study, the use of exfoliation‐restacking strategy to prepare mesoporous nanohybrids of 2D Nickel‐chromium‐layered double hydroxide (Ni‐Cr‐LDH) nanosheets pillared with polyoxovanadate (POV) anions (Ni‐Cr‐LDH‐POV) for a high‐performance hybrid supercapacitor (HSC) is demonstrated. The pillaring approach of Ni‐Cr‐LDH monolayers with POV anions via exfoliation‐restacking strategy yields mesoporous ordered layered structure with a high surface area and interconnected network morphology. The pillared hybridization of Ni‐Cr‐LDH with POV anions boosts the electrochemical performance of the pristine Ni‐Cr‐LDH, which is attributed to the development of layer‐by‐layer stacking structure with expanded gallery height and high surface area interconnected network morphology. The Ni‐Cr‐LDH‐POV nanohybrid electrode exhibits an improved specific capacity of 294.5 mAh g −1 as compared to pristine Ni‐Cr‐LDH electrode (98.9 mAh g −1 ) at 1 mA cm −2 with 82% capacity retention after 5000 charge‐discharge cycles. A full‐cell HSC composed of mesoporous Ni‐Cr‐LDH‐POV nanohybrid as a cathode and reduced graphene oxide (rGO) as an anode delivers a maximum specific energy of 57.78 Wh kg −1 and specific power of 1.59 kW kg −1 with 87% cyclic durability over 10 000 charge‐discharge cycles. The present study demonstrates the usefulness of the pillared Ni‐Cr‐LDH‐POV nanohybrids via exfoliation‐restacking strategy for exploring high‐performance HSC.