Multi‐walled carbon nanotubes supported copper phosphate microflowers for flexible solid‐state supercapacitor
Akanksha Agarwal, Sutripto Majumder, Babasaheb R. Sankapal
Abstract
Factual realization of 2-fold material mutualistic approach has been demonstrated as a state-of-art for the growth of copper phosphate (Cu2P2O7) microflowers on multi-walled carbon nanotubes (MWCNT) through simple, low cost, and industry-scalable chemical route, namely, successive ionic layer adsorption and reaction. Rationally designed unique surface architecture synergistically comprehends the merits of highly conductive electric double-layer capacitance-based MWCNT skeleton and pseudocapacitance enriched Cu2P2O7 enabling Cu2P2O7/MWCNT (CuCNT) composite. As-synthesized CuCNT electrode exhibits reciprocity toward exceptionally enhanced electrochemically active surface area of 398.6 m2 g−1, high specific capacitance of 465 F g−1 at 13 A g−1, and extraordinary cyclic stability. Comparative accounting of charge storage in terms of surface-capacitive and diffusion-controlled mechanisms has been explored in depth to gain insight into internal electrochemical kinetics. Furthermore, symmetrically configured bendable solid-state supercapacitor device using CuCNT delivers proficient specific energy of 25.4 Wh kg−1 together with high mechanical stability of 96% at 170° of bending. Also, the experimentally and theoretically evaluated series and parallel combination of two devices serve as a showcase toward potential candidature for applications of specific requirements. Furthermore, live demonstration through lightening of 21 red light-emitting diodes authorizes the probable commercialization of the present CuCNT device.