Nitrogen and phosphorus co-doped hierarchically porous carbons derived from cattle bones as efficient metal-free electrocatalysts for the oxygen reduction reaction. Issue 46 (14th November 2017)

• Record Type: Journal Article
• Authors: Zan, Yongxi; Zhang, Zhengping; Liu, Haijing; Dou, Meiling; Wang, Feng
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 46(2017)
• Page Start: 24329
• Page End: 24334
• Publication Date: 2017-11-14
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c7ta07746g
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Nitrogen and phosphorus co-doped cattle-bone-derived hierarchically porous carbon metal-free electrocatalysts were synthesized exhibiting superior oxygen reduction performance than Pt/C. Abstract : The development of highly efficient metal-free electrocatalysts towards the oxygen reduction reaction (ORR) is of vital importance for the large-scale application of fuel cell technologies. Herein, we demonstrate a facile and effective strategy for the controllable synthesis of nitrogen and phosphorus co-doped hierarchically porous carbon (N, P-HPC) electrocatalysts by pyrolyzing phytic acid (PA) and dicyandiamide (DCDA) with nitrogen-doped hierarchically porous carbon (NHPC) derived from cattle bones. The results show that optimal N and P co-doping plays an important role in enhancing the ORR catalytic activity of carbon-based electrocatalysts. The optimized N, P-HPC with a high content of N (3.2 at%) and P (4.0 at%) exhibits remarkable ORR activity with an onset potential of 0.924 V (comparable to commercial Pt/C), a half-wave potential of 0.853 V (12 mV higher than that of Pt/C) and a kinetic current density of 38.2 mA cm −2 at 0.8 V (1.9-times that of Pt/C) in alkaline electrolyte. Furthermore, the N, P-HPC electrocatalyst also demonstrates superior electrochemical stability and methanol tolerance in comparison with Pt/C. The excellent ORR performance of N, P-HPC can be attributed to the increased number of active sites, the favorable three-dimensional hierarchically porous structure and the large specific surface area (1516 m 2 g −1 ). This attractive strategy opens a new avenue for the synthesis of highly efficient metal-free electrocatalysts for the ORR.