Inexpensive synthesis route of porous polyaniline–ruthenium oxide composite for supercapacitor application

• The PANI–RuO2 composite thin films have been synthesized by simple and inexpensive SILAR method.
• The PANI–RuO2 composite thin film electrode exhibited specific capacitance of 664 F g−1.
• The PANI–RuO2 composite thin film shows enhanced stability over 5000 cycles.

Porous polyaniline–ruthenium oxide composite has been synthesized using a successive ionic layer adsorption and reaction (SILAR) method. The result of X-ray diffraction indicates the amorphous nature of polyaniline–ruthenium oxide (PANI–RuO2) composite. Fourier transform infrared (FT-IR) and FT-Raman spectroscopy studies reveal the formation of composite material. The morphology of PANI–RuO2 composite observed using scanning electron microscope (SEM) shows hierarchical nanofibers with small particles grown on the nanofibers. The electrochemical measurement shows that PANI–RuO2 composite electrode material yields specific capacitance of 664 F/g and higher capacitance retention (89%) of its initial capacitance after 5000 cycles. The unique structure of PANI–RuO2 composite and the coexistence of conducting PANI with RuO2 are found to be responsible for the superior electrochemical properties.