Photon-Driven Nitrogen Fixation: Current Progress, Thermodynamic Considerations, and Future Outlook

Abstract

Over the last century, the industrialization of agriculture and the consumption of fossil fuels have resulted in a significant imbalance and redistribution in nitrogen-containing resources. This has sparked an interest in developing more sustainable and resilient approaches for producing nitrogencontaining commodities such as fertilizers and fuels. One largely neglected but emerging approach is photocatalytic nitrogen fixation. There is significant evidence that this process occurs spontaneously in terrestrial settings, and it has been demonstrated in numerous engineered systems. Yet many questions still remain unanswered regarding the rates, mechanisms, and impacts of photocatalytically producing fixed nitrogen "out of thin air". This work reviews the fascinating history of the reaction and examines current progress toward understanding and improving photofixation of nitrogen. This is supplemented by a quantitative review of the thermodynamic considerations and limitations for various reaction mechanisms. Finally, future prospects and preliminary performance targets for photocatalytic nitrogen fixation are discussed.

Keggin‐Type Polyoxometalate‐Based ZIF‐67 for Enhanced Photocatalytic Nitrogen Fixation

“…[1][2][3][4] Fixing N 2 is the necessaryr eaction for globale cosystem cycle, and the corresponding productiono fN H 3 is in urgent demandw ith wide applications in the agricultural industry,t he pharmaceutical industry,a nd energy storage. [5][6][7][8] In fact, population growth and social development are positivelyc orrelated with NH 3 output.A tp resent, N 2 fixation by naturald initrogenase is far below the standard required owing to sharply increased demands. [9,10] NH 3 is synthesized by the Haber-Bosch approach in very harsh conditions involving of high purity N 2 and H 2 ,w hichi sa ccompanied with the disadvantages of low productivity, release of ag reat deal of greenhouse gases,a nd massive energy consumption.…”

Pothole‐rich Ultrathin WO3 Nanosheets that Trigger N≡N Bond Activation of Nitrogen for Direct Nitrate Photosynthesis

“…[7][8][9][10][11][12][13] Theh igh value-added nitrate products are used as araw ingredient for the production of chemical fertilizer,g unpowder,a nd explo-sives,w hich are of crucial importance to feed the population and defend the national security. [14] Therefore,t he industrial nitrogen fixation to nitrate,b ased on ammonia oxidation, followed by am ulti-step chemical reaction, has been developed and employed, [15,16] but the harsh reaction conditions (i.e.15-25 MPa, 673-873 K, and noble metals) force scientists to seek amore moderate nitrogen fixation approach.…”

Overcoming Chemical Inertness under Ambient Conditions: A Critical View on Recent Developments in Ammonia Synthesis via Electrochemical N2 Reduction by Asking Five Questions

“…20–40 GJ are needed to produce 1 t of NH 3 . A further problematic aspect that is sometimes overlooked is the very localized character of NH 3 production . H‐B plants are huge facilities with large capacity to decrease production costs.…”