Facile Synthesis of Microstrip-Like Copper Phosphate Hydroxide Thin Films for Supercapacitor Applications

Binder-free copper phosphate hydroxide [Cu-2(PO4)(OH)] thin films have been prepared on stainless-steel (SS) substrates at 393 K via a facile hydrothermal method. X-ray diffraction analysis confirmed the formation of orthorhombic-structured copper phosphate hydroxide [Cu-2(PO4)(OH)] thin films with uniform microstrip-like morphology and Brunauer-Emmett-Teller (BET) surface area of 5.26 m(2) g(-1). The electrochemical performance of the films depended on their thickness, with a maximum specific capacitance of 280 F g(-1) at a scan rate 5 mV s(-1) in 1 M KOH electrolyte. The [Cu-2(PO4)(OH)] electrode delivered an energy density of 3.85 Wh kg(-1) and a power density of 264.70 W kg(-1) with excellent (91%) capacitive retention after 2000 cycles. This excellent electrochemical performance shows that such microstrip-like Cu-2(PO4)(OH) thin films are promising electrodes for high-performance supercapacitors. [GRAPHICS] .