Surface engineering of Au nanostructures for plasmon-enhanced electrochemical reduction of N2 and CO2 into urea in the visible-NIR region

G. Bharath, G. Karthikeyan, Anuj Kumar, J. Prakash, Devanand Venkatasubbu, Ashok Kumar Nadda, Vijai Kumar Gupta, Mohammad Abu Haija and Fawzi Banat

Applied Energy, 2022, vol. 318, issue C, No S0306261922006031

Abstract: The photoelectrochemical reduction of CO2 and N2 (N2CO2RR) is a promising method of producing urea under ambient conditions since highly active and stable electrocatalysts are desired. Plasmonic metals have attracted considerable attention due to their enhanced electrochemical activity at visible and near-infrared wavelengths (NIR). Herein, the morphology of Au was tuned to spherical nanoparticles, nanorods, and nanosheets by utilizing a variety of structure-directing agents. Among them, Au nanosheets (Au NSs) can absorb a broad spectrum of NIR wavelengths, enabling electrochemical reduction of N2 into NH3, with high yield rates and higher Faradic efficiency (FE) than most of the N2RR results reported. In addition, a distal associative pathway for N2RR into NH3 has been established over Au NSs. Additionally, the Au NSs photocathode demonstrates high stability over a period of 10 consecutive runs. In addition, this work provides a guide to fabricating highly stable photocathodes that convert N2 and CO2 into urea. Au NSs photocathode achieves a maximum urea yield rate of 98.5 µgureamgcat-1h−1 and FE of 22.7% at −0.7 V vs. RHE. Results show that the N2 and CO2 is the primary factor for urea production, whereas reducing NO3– and HCO3– contributes significantly to the total urea yield rate. Density functional theory calculations (DFT) reveal that Au NSs play a crucial role in promoting N2 and CO2 adsorption, activation, and stimulating the coupling reaction between C-N to form urea by the distal mechanism. As a result, this work opens up the possibility of developing hybrid catalytic systems for simultaneously reducing nitrate-containing wastewater and CO2, thus producing urea-rich treated water for agricultural use and achieving carbon neutrality.

Keywords: Plasmonic metals; N2 reduction reaction; N2 and CO2 reduction reaction; Ammonia production; Urea production (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261922006031
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:318:y:2022:i:c:s0306261922006031

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2022.119244

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().