02821nas a2200313   4500008004100000245018800041210006900229260000800298300001600306490000600322520168400328653002302012653001802035653003302053653003202086653002002118653003302138653002202171100002002193700001602213700001702229700001702246700002002263700001902283700002402302700002602326700002402352856013102376       2022                        eng d00aFirst-principles investigation of the electrocatalytic reduction of CO2 on zirconium-based single-, double-, and triple-atom catalysts anchored on a graphitic carbon nitride monolayer0 aFirstprinciples investigation of the electrocatalytic reduction   cOCT  a15409-154170 v53 a<p>
	Conversion of carbon dioxide (CO2) with the help of an appropriate electrocatalyst with high stability, low onset potential, and exceptional selectivity is still one of the great tasks in the electrocatalytic reduction of CO2 to valuable chemicals. Herein, by means of systematic first-principles simulations, we investigate the CO2 reduction reaction (CO2RR) activity of zirconium-based single-, double-, and triple-atom (Zrn@C2N; n = 1-3) catalysts anchored on a graphitic carbon-nitride monolayer. In tune with the Sabatier principle, our results reveal that a moderate CO2 binding is vital for a low onset potential for the CO2RR. Consequently, based on rigorous free energy calculations, the Zr-based single-atom catalyst (SAC) is found to be most effective to convert CO2 to valuable products such as HCOOH and CH3OH. It is worth noting that CO2 reduction to HCOOH is spontaneous via the *HCOO intermediate on Zr1@C2N and involves a low onset potential of -0.23 V with respect to the reversible hydrogen electrode from the *COOH intermediate. Among all the catalysts evaluated computationally, the Zr SAC further reveals the lowest onset potential of -0.89 V for CH3OH formation. The results show that the Zr-based catalysts especially Zr1@C2N are found to effectively suppress the competitive hydrogen evolution reaction and promote the CO2RR. Moreover, all three catalysts exhibit high kinetic and thermal stability with negligible distortion due to which their structures can be retained very well up to 600 K. Thus, the current work may provide effective catalyst-design strategies for enhancing the electrocatalytic CO2RR performance of Zr-based materials.</p>
10aC1 and C2 products10aCO2 reduction10afirst-principles simulations10ahydrogen evolution reaction10aonset potential10asingle-atom catalysts (SACs)10aZrn@C2N catalysts1 aHassan, Afshana1 aAnis, Insha1 aShafi, Sadaf1 aAssad, Assif1 aRasool, Anjumun1 aKhanam, Romana1 aBhat, Gulzar, Ahmad1 aKrishnamurty, Sailaja1 aDar, Manzoor, Ahmad  uhttps://library.ncl.res.in/content/first-principles-investigation-electrocatalytic-reduction-co2-zirconium-based-single-double01908nas a2200193   4500008004100000022001400041245009800055210006900153260000900222300001600231490000600247520122300253100001601476700002201492700002401514700002901538700002401567856012301591       2022                        eng d  a2470-134300aProbing the site-specific reactivity and catalytic activity of Ag-n (n=15-20) silver clusters0 aProbing the sitespecific reactivity and catalytic activity of Ag  cJUN   a19687-196930 v73 a<p>
	Density functional theory calculations within the framework of generalized gradient approximation (GGA), meta-GGA, and local functionals were carried out to investigate the reactivity and catalytic activity of Ag-n (n = 15-20) clusters. Our results reveal that all the Ag-n dusters in this size range, except Ag-20, adsorb O-2 preferably in the bridged mode with enhanced binding energy as compared to the atop mode. The O-2 binding energies range from 0.77 to 0.29 in the bridged mode and from 0.36 to 0.15 eV in the atop mode of O-2 adsorption. The strong binding in the case of the bridged mode of O-2 adsorption is also reflected in the increase in O-O bond distance. Natural bond orbital charge analysis and vibrational frequency calculations reveal that enhanced charge transfer occurs to the O-2 molecule and there is significant red shift in the stretching frequency of O-O bond in the case of the bridged mode of O-2 adsorption on the clusters, thereby confirming the above results. Moreover, the simulated CO oxidation reaction pathways show that the oxidation of the CO molecule is highly facile on Ag-16 and Ag-18 clusters involving small kinetic barriers and higher heats toward CO2 formation.</p>
1 aAnis, Insha1 aDar, Mohd, Saleem1 aBhat, Gulzar, Ahmad1 aRather, Ghulam, Mohammad1 aDar, Manzoor, Ahmad  uhttps://library.ncl.res.in/content/probing-site-specific-reactivity-and-catalytic-activity-ag-n-n15-20-silver-clusters