Platinized titanium nitride/graphene ternary hybrids for direct methanol fuel cells and titanium nitride/graphene composites for high performance supercapacitors. (1st December 2016)

• Record Type: Journal Article
• Authors: Haldorai, Yuvaraj; Arreaga-Salas, David; Rak, Choe Sang; Huh, Yun Suk; Han, Young-Kyu; Voit, Walter
• Is Part Of: Electrochimica acta. Volume 220(2016)
• Page Start: 465
• Page End: 474
• Publication Date: 2016-12-01
• Subjects: Methanol oxidation -- titanium nitride -- graphene -- electrocatalyst -- supercapacitor; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.10.130
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: A titanium nitride/reduced graphene oxide nanocomposite (TiN/rGO) was fabricated by a two-step process. The resulting TiN particles had a mean diameter of less than 10 nm and were densely decorated onto the rGO surface. The TiN/rGO composite was used as a support matrix to anchor platinum (Pt) nanoparticles by the polyol method to fabricate a Pt@TiN/rGO ternary hybrid catalyst for methanol oxidation. An increase in the methanol oxidation current density was observed for Pt@TiN/rGO when compared to Pt/rGO and Pt/Vulcan, confirming that the inclusion of TiN along with rGO improved the electrocatalytic activity. The electrochemical surface area was also significantly higher for the Pt@TiN/rGO catalyst (84.5 m 2 g −1 ) than for Pt/rGO (51.7 m 2 g −1 ) and Pt/Vulcan (33.7 m 2 g −1 ), highlighting the importance of TiN. The Pt@TiN/rGO hybrid showed excellent electrocatalytic activity, long-term stability, and better carbon monoxide tolerance for the electrooxidation of methanol when compared to more traditional catalysts, namely Pt/rGO and Pt/Vulcan with same Pt content. Conversely, the TiN/rGO composite (without Pt) showed a higher capacitance of 415 F g ‐1 and a long cycle life, with 7.0% capacitance loss after 10, 000 cycles. The capacitance was as high as 275 F g ‐1 at a current density of 5 A g ‐1 .