Recent Progress in Computational Design of Single-Atom/Cluster Catalysts for Electrochemical and Solar-Driven N₂ Fixation

Abstract

Fixation of dinitrogen into ammonia is an essential biological process for the evolution of life, and at the same time ammonia is an essential component for many industrial processes, including fertilizers, plastics, and so on. NH 3 is also known as the best alternative to H 2 in fuel cells. However, due to chemical inertness, direct conversion of N 2 into NH 3 is not possible; a suitable catalyst is required. The century-old Haber−Bosch process, utilizing an Fe-based catalyst, is extremely energy-intensive and eco-unfriendly due to the consumption of fossil fuels. In recent years, huge development has taken place in the design and applications of suitable electro-and photocatalysts for artificial N 2 fixation. First-principles calculations have been considered as a powerful avenue for theoretical screening of promising catalysts through rational design and analysis of the plausible mechanisms or pathways of reactions. The present review focuses on recent theoretical developments of various unsupported nanoclusters and supported single-atom and cluster catalysts for application in electro-and photochemical N 2 reduction reactions. The support substrates include oxides, carbides, nitrides of metal-based 2D materials, porous carbonaceous materials, and metal-free 2D materials containing main-group elements like B, C, N, and P. Although some reviews have already been made, focusing on the research related to either electro-or photocatalytic N 2 fixation on different catalysts, here we give a comprehensive account of both electrochemical and photochemical nitrogen reduction reaction (NRR) activities and selectivities of various supported single-atom and polyatomic cluster catalysts. Additionally, a comparative assessment is made on the basis of free energy of adsorption, most favorable pathway, potential limiting step, and corresponding limiting potential of the NRR.

PtTe2/Sb2S3 Nanoscale Heterostructures for the Photocatalytic Direct Z-Scheme with High Solar-to-Hydrogen Efficiency: A Theoretical Investigation

“…However, Kuznetsov et al reported experimentally that the Gibbs free energy in HER for the MXene phase of Mo 2 CT x can be substantially decreased and approach zero by the synthesis of a solid solution of the Mo 2 CT x :Co MXene phase with cobalt substitution on the molybdenum sites and without a post-synthetic modification of the parent MXene. Similarly, the S or Te atom can also be added to the PtTe 2 or Sb 2 S 3 monolayer and form a solid solution of PtTe 2 :S or Sb 2 S 3 :Te to reduce the Gibbs free energy . It indicates that the present PtTe 2 /Sb 2 S 3 heterostructure with a normalΔ G normalH * of 1.145–1.396 eV can also drive HER feasibly.…”

“…Similarly, the S or Te atom can also be added to the PtTe 2 or Sb 2 S 3 monolayer and form a solid solution of PtTe 2 :S or Sb 2 S 3 :Te to reduce the Gibbs free energy. 63 It indicates that the present PtTe 2 /Sb 2 S 3 heterostructure with a G H * of 1.145−1.396 eV can also drive HER feasibly.…”

Catalytic active centers beyond transition metals: atomically dispersed alkaline-earth metals for the electroreduction of nitrate to ammonia

“…In addition, to further verify the thermodynamical stability of the AE-SAC systems, the energy difference (Δ E b ) between E b and E coh was calculated. 64 In which, E coh is the cohesive energy of AE metal bulk and can be calculated using the formula of E coh = ( E bulk – nE AE )/ n , where E bulk is the total energy of the AE metal crystal and n is the number of metal atoms in the crystal. A negative Δ E b indicates that the AE metal single atom tends to remain isolated on the substrate rather than agglomerate, and a more negative Δ E b means higher thermodynamical stability.…”

Optimizing the NRR activity of single and double boron atom catalysts using a suitable support: a first principles investigation

“…17,18 Until now single and double atom catalysts (SACs and DACs) of different transition metals with variable supports have been screened efficiently both experimentally and theoretically, leading to various design principles and important generalizations for catalyst design with respect to the NRR. 19–42 Along similar directions, there has been a greater demand to design transition metal free catalysts (TMFCs) for the NRR due to their promising catalytic activity and durability. In addition, the cheap and abundant nature of TMFCs makes their development for N 2 reduction highly imperative from an economic point of view.…”