Over 21.0% faradaic efficiency of ambient ammonia production: Photoelectrocatalytic activity of MOF-235. (August 2022)

• Record Type: Journal Article
• Authors: Camargo, Luan Pereira; da Silva, Paulo Rogério Catarini; Batagin-Neto, Augusto; Klobukoski, Vanessa; Vidotti, Marcio; Dall'Antonia, Luiz Henrique
• Is Part Of: Applied materials today. Volume 28(2022)
• Publication Date: 2022-08
• Subjects: Nanoscale materials -- Photoelectrocatalysis -- Semiconductor -- Solvothermal synthesis; Materials science -- Periodicals; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1016/j.apmt.2022.101540
• Languages: English
• ISSNs: 2352-9407

Abstract

Highlights: MOF-235 as highly efficient NRR photoelectrocatalyst under UV light MOF-235 exhibits high Faraday efficiency for NRR under ambient conditions The active sites of MOF-235 are related with the trinuclear-oxocentered iron Abstract: In recent years, the Haber-Bosh process's ammonia synthesis has shown a lot of energy consumption and significant CO2 emissions. In this sense, the photoelectrochemical production of NH3 via dinitrogen fixation has been showing a promising strategy. Thus, in this work, ammonia production under photoelectrocatalytic condition was carried out using the metal-organic iron terephthalate structure (MOF-235), obtained by a simple and low-cost process (solvothermal). The results indicated greater activity for the nitrogen reduction reaction (NRR) compared to the hydrogen reduction reaction (HRR), in addition to a high yield of NH3 0.716 µg h −1 cm −2 and Faradaic efficiency greater than 21.0% at - 0.2 V vs reversible hydrogen electrode in 0.1 mol L −1 Na2 SO4 electrolyte. It is believed that the good results of MOF-235 during NRR are related to a high specific area of MOF, making available active sites of trinuclear-oxocentered iron in abundance. The material homogeneity in the electrode and the excellent light absorption were also decisive factors for the supply of high energy electrons necessary for ammonia production. Graphical Abstract: Image, graphical abstract