A Bifunctional Catalyst for Green Ammonia Synthesis from Ubiquitous Air and Water.

Ammonia (NH 3 ) is essential for modern agriculture and industry, and due to its high hydrogen density and no carbon emission, NH 3 is also expected to be the next-generation of "clean" energy carrier. Herein, directly from air and water, the plasma-electrocatalytic reaction system for NH 3 production, which combines two steps of plasma-air-to-NO x - and electrochemical NO x - reduction reaction (eNO x RR) with a bifunctional catalyst, have been successfully established. Especially, the bifunctional catalyst of CuCo 2 O 4 /Ni can simultaneously promote the plasma-air-to-NO x - and eNO x RR processes. The easy adsorption and activation of O 2 by CuCo 2 O 4 /Ni greatly improve the NO x - production rate at the first step. Further, CuCo 2 O 4 /Ni can also resolve the over bonding of the key intermediate of *NO, and thus reduce the energy barrier of the second step of eNO x RR. And finally, the "green" NH 3 production achievs the excellent FE NH3 (96.8%) and high-record NH 3 yield rate of 145.8 mg h -1 cm -2 with large partial current denstity (1384.7 mA cm -2 ). Moreover, an enlarged self-made H-type electrolyzer improves the NH 3 yield to be 3.6 g h -1 , and the obtained NH 3 is then rapidly converted to a solid of magnesium ammonium phosphate hexahydrate, which favors the easy storage and transportation of NH 3 . This article is protected by copyright. All rights reserved.