Remarkable reactivity of Fe modified Cu(100) surface towards CO2 decomposition: A DFT study

First principle calculations have been performed on Fe doped Cu(100) slab model systems employing GGA at PW-91 level to study the carbon dioxide (CO2) reduction. Some important calculations were repeated with PBE functional too. The top layer of Cu (100) has been tailored with Fe atoms. The process has been completed using atom by atom replacement of Cu atoms by Fe atom(s) up to 4 substitutions. It is observed that adsorption energy (Eads) of CO2 on the systems studied is significant. The Eads of CO2 lies in the range of -0.78 to -1.09 eV depending upon the Fe concentration and the adsorption site/functional used. It is observed that a small 5.55% Fe concentration (2 Fe atoms) when doped linearly dissociate the molecule effectively surmounting a small barrier of 0.30 eV through exothermic process (-1.22 eV) after adsorbing CO2 with catalytically efficient mo-lecular adsorption energy around -1.0 eV. Thus our investigations report a land mark achievement regarding CO2 decomposition into CO and O-atoms due to synergic effect of Fe and Cu.