Bismuth hollow nanospheres for efficient electrosynthesis of ammonia under ambient conditions

Electrochemical synthesis of NH3, when coupled with renewable energy, provides an attractive alternative to the energy- and capital-intensive Haber-Bosch process. Crucial to enabling this vision is the development of highly active and selective catalysts for the electrochemical nitrogen reduction reaction (ENRR). Herein, we report a facile synthesis of hollow and solid bismuth (Bi) nanospheres catalysts using a one-pot solvothermal method. As a consequence of its hierarchical macroporous-mesoporous architecture, Bi hollow nanospheres catalyst exhibited significantly improved catalytic performance towards the ENRR compared with its solid counterpart. Remarkably, the Bi nanocatalyst enabled ammonia electrosynthesis with a yield of 23.4 1.3 lig 11-1 mg-lcat. and a corresponding FE as high as 19.8 1.1% at ambient conditions, which outperformed most ENRR catalysts reported up to date. (C) 2020 Elsevier B.V. All rights reserved.