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[Display omitted] • FLP-UiO-67 catalysts set new standards in CO 2 to formic acid conversions. • −B(CH3)2 group assisted heterolytic dissociation of H 2 in the advances CO 2 hydrogenation efficiency benchmarks. • Innovative UiO-67 framework with FLPs boosts catalytic performance. In this study, we explore the potential of metal–organic frameworks (MOFs) as catalysts for converting CO 2 into valuable chemicals. The focus is on integrating frustrated Lewis pairs (FLPs) within the UiO−67 framework. We investigated 12 distinct functionalized FLP moieties (X = −BF 2 , −BCl 2 , −BBr 2 , −BH 2 , −B(CH 3) 2 , −B(CF 3) 2 , −B(CN) 2 , −B(NO 2) 2 , −B(OH) 2 , −B(NH 2) 2 , −B(OCH 3) 2 , and −B(N(CH 3) 2) 2 to determine their ability to activate small molecules within heterogeneous catalysis using density functional theory (DFT). This study reveals two critical stages in the CO 2 conversion process with H 2 in UiO−67−X. First, the initial heterolytic cleavage of H 2 at the FLP site, and second, the subsequent hydrogenation of CO 2. The latter involves the addition of a hydride and a proton. Our findings demonstrate that these modifications facilitate efficient dissociation of H 2 into Hδ− and Hδ+ with energy barriers ranging from 0.12 to 0.87 eV and CO 2 hydrogenation barriers spanning from 0.61 to 1.90 eV. Notably, the −B(CH 3) 2 functional group exhibited superior effectiveness in CO 2 hydrogenation to formic acid (HCOOH; FA). This enhanced activity correlates directly with FLP acidity and the Gibbs free energy changes in H 2 dissociation reaction. It highlights the significant influence of FLP−assisted heterolytic dissociation of H 2 in the CO 2 conversion process. The results of this study do more than introduce metal-free heterogeneous FLPs within MOFs. They also establish a clear link between the functional group composition, FLP acidity, and catalytic efficiency. These insights offer a valuable theoretical foundation for the design of advanced UiO−67−X catalysts. They open up possibilities for transforming greenhouse gases into valuable chemical products, contributing to sustainable chemical synthesis. [ABSTRACT FROM AUTHOR]

• Our proposed pathway of CO 2 hydrogenation on required the significantly small energy barrier of 0.63 eV compared to graphene base catalyst. • The presence of CO 2 can help to facilitate hydrogen dissociation and hydrogenation reactions to produce the FA on the Pt-BV catalyst. • Hydrogen dissociation step an important role as rate determining step of CO 2 hydrogenation. • The carboxylate route is found to be more energetically and kinetically feasible rather than that it is formate route. In this work, we investigated the mechanism of CO 2 hydrogenation over the Pt-doped boron nitride nanosheets (Pt-BNNSs) by using the density functional theory (DFT). It is found that a Pt adatom can be effectively stabilized in boron vacancy site (Pt-BV). Our investigation shows that the reaction mechanisms of CO 2 hydrogenation over Pt-BV can be found in three possible reaction pathways: (i) co-adsorption, (ii) H 2 dissociation, and (iii) co-adsorption together with H 2 dissociation pathways. The co-adsorption together with H 2 dissociation provides the most favorable pathway among of these three proposed mechanisms. The important finding of our study is that the presence of CO 2 in step of hydrogen dissociation plays an important role in producing the FA on the Pt-BV catalyst. Moreover, we found that the hydrogenation of CO 2 via carboxylate (COOH) has the rate-determining step of 0.63 eV in the step of hydrogen dissociation. In addition, the microkinetic modelling suggests that the COOH route is found to be more energetically and kinetically feasible rather than that it is formate route (HCOO) with the reaction temperature at 350 K and pressure of 5 bar. Our calculation results provide an important information for developing Pt-BV catalysts and might shed light on experimental design the novel Pt-BV catalyst for the CO 2 hydrogenation and the conversion of greenhouse gases into value-added products. The presence of CO 2 can help to facilitate hydrogen dissociation and hydrogenation reactions to produce the FA on the Pt-BV catalyst. The rate determining step of formic acid decomposition is significantly lower (0.63 eV) compared to others graphene base catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]