Phthalocyanine and single-walled carbon nanotube-decorated hybrid material: design, photophysical properties and high-performance supercapacitor applications

Abstract

Supercapacitors have emerged as leading energy storage devices due to their remarkable capacitance, high power output and exceptional cycle life. Flexible and binder-free nanomaterials play a crucial role in improving device performance and integration. Herein, we describe the synthesis of a zinc phthalocyanine derivative, TSA–ZnPc, which incorporates thiosalicylic acid (TSA) units, and its integration with single-walled carbon nanotubes (SWCNTs) to fabricate a flexible and free-standing hybrid electrode (TSA–ZnPc–SWCNT). TSA–ZnPc was characterized by NMR, FTIR, and MALDI-TOF-MS, and its optical properties were investigated using UV-vis and fluorescence spectroscopy. The nanohybrid was assembled through noncovalent van der Waals, π–π and S–π interactions without the use of binding agents, forming smooth, interconnected SWCNT networks. This was confirmed by SEM and AFM analyses. Electrochemical measurements (CV, GCD and EIS) revealed a specific capacitance of 82.1 F g⁻¹ at 1 mV s⁻¹ with an excellent stability over 12 000 cycles, highlighting its strong potential for next-generation renewable energy-storage applications.