AUTHOR=Kumar Subodh , Aziz S. K. Tarik , Kumar Sushil , Riyajuddin Sk , Yaniv Gili , Meshi Louisa , Nessim Gilbert D. , Ghosh Kaushik 

TITLE=Three-Dimensional Graphene-Decorated Copper-Phosphide (Cu3P@3DG) Heterostructure as an Effective Electrode for a Supercapacitor

JOURNAL=Frontiers in Materials

VOLUME=7

YEAR=2020

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2020.00030

DOI=10.3389/fmats.2020.00030

ISSN=2296-8016

ABSTRACT=<p>Transition metal phosphides already emerged with great interest due to their energy storage capacitance, superior metalloid characteristics, and decent electrical conductivity. To achieve a commercially viable outcome, these electrodes are fabricated with interconnected carbonaceous materials. Herein, we have synthesized hexagonal copper phosphide (Cu<sub>3</sub>P) platelets using chemical vapor deposition (CVD) and integrated it with highly conducting three-dimensional graphene (3DG), leading to a nanohybrid (Cu<sub>3</sub>P@3DG) as a coulombic efficient supercapacitor. This nanohybrid has exhibited a specific capacitance (C<sub>sp</sub>) of 1,095.85 F/g at 10 mV/s scan rate along with a cycling stability of 95% capacitive retention after 3,000 cycles at a current density of 8.97 A/g. The C<sub>sp</sub> is almost four times higher and the stability is 1.2 times higher compared to the bare Cu<sub>3</sub>P platelets. We have fabricated an asymmetric supercapacitor (ASC) using Cu<sub>3</sub>P@3DG on graphite as cathode and activated carbon (AC) on graphite as anode (Cu<sub>3</sub>P@3DG//AC) that has shown high specific capacity (108.78 F/g), energy density (8.23 Wh/kg), and power density (439.6 W/kg). Moreover, this ASC has exhibited an excellent life cycle (5,500 consecutive charge–discharge with 96% coulombic efficiency). Therefore, the proposed all-solid-state hybrid device can be considered as a route for next-generation high-performing energy storage devices.</p>