(Lecture, May 24) Precious metal-free Electrocatalysts for High-Efficiency Ammonia Production from Water and Nitrogen
2018-05-14 readCount:139
Speaker: Prof. Wu Gang (University at Buffalo, the State University of New York)
Venue: Room 214, Building No.16, Wushan Campus
Time: Thursday, May 24, 2018, 9:00-10:30
Sustainable synthesis of Ammonia (NH3) is gaining great attention not only for its application as an alternative renewable energy fuel but also to substitute production of ammonia through the conventional Haber Bosh process. The conventional Haber-Bosh uses fossil fuels in deriving hydrogen from steam reforming of natural gas, is energy intensive and also leads to significant CO2 emission. Alternatively, electrochemical synthesis of ammonia (ESA) using renewable energy through the nitrogen reduction reaction (NRR) in alkaline medium saves the use of hydrogen as a reactant as the aqueous electrolyte forms the source of proton. However, the standard reduction potential of nitrogen and hydrogen fall in the same domain. Thus, hydrogen evolution reaction is so dominant at the applied potential that selectivity of nitrogen reduction is a major challenge in the budding field. Herein, we report a metal-organic framework-derived nitrogen-doped metal free nanoporous carbon electrocatalyst with a Faradaic efficiency (FE) of 10 % at -0.3 V vs RHE under ambient conditions for the NRR. It exhibits a remarkable production rate of NH3 up to 3.4×10-6 mol cm-2 h-1 using aqueous 0.1 M KOH electrolyte. The performance has been compared with other N doped carbon derived from commercial polyaniline and nitrogen free KJ black and N doped CNT. The stability of the nitrogen-doped electrocatalyst was demonstrated during an 18-hour continuous test with constant production rates. This work provides a new insight into the rational design and synthesis of nitrogen-doped and defect-rich carbon NRR catalysts for NH3 synthesis at ambient conditions.
Gang. Wu is an associate professor from Department of Chemical and Biological Engineering, University at Buffalo, the State University of New York, Buffalo, New York 14260, United States.

Announced by School of Chemistry and Chemical Engineering