Facile synthesis of carbon encapsulated RuO₂ nanorods for supercapacitor and electrocatalytic hydrogen evolution reaction

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>In this work, carbon encapsulated RuO<SUB>2</SUB> nanorods (RuO<SUB>2</SUB> NRs/C) has been synthesized by thermolysis of ruthenium chloride and <I>Punica granatum</I> (<I>P. granatum</I>) peel under N<SUB>2</SUB> atmosphere. The synthesized RuO<SUB>2</SUB> NRs/C was characterized using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction method (XRD), field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) analyses. The FT-IR results suggested that the organic constituents of <I>P. granatum</I> have been carbonized and encapsulated over RuO<SUB>2</SUB> nanorods (RuO<SUB>2</SUB> NRs). The XRD pattern of RuO<SUB>2</SUB> NRs/C revealed its crystalline nature and carbon encapsulation. The synthesized RuO<SUB>2</SUB> NRs/C has been well dispersed with the average width of 20 nm, exposed from the FE-SEM and HR-TEM images. The EDS results of RuO<SUB>2</SUB> NRs/C showed the existence of three elements viz., Ru, O and C. Further, the supercapacitor and electrocatalytic hydrogen evolution reaction (HER) activities of RuO<SUB>2</SUB> NRs/C were studied using standard electrochemical methods. The synthesized RuO<SUB>2</SUB> NRs/C offered a maximum specific capacitance of 151.3 F g<SUP>−1</SUP> at a scan rate of 5 mV s<SUP>−1</SUP>, obtained from the cyclic voltammetry results. The onset over potential and Tafel slope of synthesized RuO<SUB>2</SUB> NRs/C for HER were −0.099 V<SUB>RHE</SUB> and −99.4 mV dec<SUP>−1</SUP>, respectively. The present study revealed that RuO<SUB>2</SUB> NRs/C as a better candidate for supercapacitor and HER.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carbon encapsulated RuO<SUB>2</SUB> nanorods (RuO<SUB>2</SUB> NRs/C) were synthesized by simple thermolysis. </LI> <LI> RuO<SUB>2</SUB> NRs/C shows good supercapacitor and electrocatalytic HER activity. </LI> <LI> RuO<SUB>2</SUB> NRs/C offered a maximum specific capacitance of 151.3 F g<SUP>−1</SUP> at 5 mV s<SUP>−1</SUP>. </LI> <LI> The onset potential and Tafel slope of RuO<SUB>2</SUB> NRs/C for HER were −0.099 V<SUB>RHE</SUB> and −99.4 mV dec<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>