Vertically Aligned Carbon Nanotube Arrays Co-doped with Phosphorus and Nitrogen as Efficient Metal-Free Electrocatalysts for Oxygen Reduction

• Published in: The journal of physical chemistry letters 2012-10, Vol.3 (19), p.2863-2870
• Main Authors: Yu, Dingshan, Xue, Yuhua, Dai, Liming
• Format: Article
• Language: English
• Subjects: Energy Conversion and Storage; Energy and Charge Transport
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/jz3011833

Using a mixture of ferrocene, pyridine, and triphenylphosphine as precursors for injection-assisted chemical vapor deposition (CVD), we prepared the first vertically aligned multiwalled carbon nanotube array co-doped with phosphorus (P) and nitrogen (N) with a relatively high P-doping level (designated as PN-ACNT). We have also demonstrated the potential applications of the resultant PN-ACNTs as high-performance electrocatalysts for the oxygen reduction reaction (ORR). PN-ACNT arrays were shown to exhibit a high ORR electrocatalytic activity, superb long-term durability, and good tolerance to methanol and carbon monoxide, significantly outperforming their counterparts doped with P (P-ACNT) or N (N-ACNT) only and even comparable to the commercially available Pt–C catalyst (45 wt % Pt on Vulcan XC-72R; E-TEK) due to a demonstrated synergetic effect arising from the co-doping of CNTs with both P and N.