In this research we investigated the generation of methanol and the utilization of CO2 using heterogeneous catalysts. Heterogeneous catalysts are frequently used in industry due to their multiple benefits, which include long-term thermal and mechanical stability, as well as reusability. Our research has demonstrated a variety of heterogeneous catalysts for sustainable methanol production and CO2 utilization, including the novel dendritic mesoporous metal oxides support. We have also designed and screened multiple active metals on the dendritic mesoporous metal oxide catalysts, modified active metal dispersion, and further reduced metal oxides to utilize silica-based catalysts, among other things. Comprehensive characterization of the final products was performed using N2 adsorption and desorption, XRD, HR-TEM, SEM, ICP-OES, XPS, H2-TPD, CO2-TPD, Raman spectroscopy, pulse-chemosorption and DRIFT, in order to determine the chemical and physical properties of the catalysts. The catalysts were found to have the following characteristics. We obtained a CO2 conversion of 25.5 % and a MeOH yield of 6.4 % after at least three cycles of usage in an avantium fixed bed reactor system with a PdCu/CZ-3 catalyst. Additionally, continuous methanol production with a higher yield (6.9 %) has been achieved using our PdZn/CZ-3 catalysts, and the best ultra-dispersed Pd nanoparticles over CZZ catalyst produces more than 12 % methanol yield with constant selectivity to methanol even after a lengthy catalytic test (more than 100 h), demonstrating their industrial viability. Additionally, our PdZn/CeTi-DMSN exhibits a high methanol production of up to 10% and better long-term stability with lower metal oxides content. The adsorption and activation of CO2 to react with the spilled over hydrogen to generate methanol has been researched for the CO2 hydrogenation and utilization reaction. Catalysts' redox, acidic, and basic characteristics all play a crucial part in this reaction and in the formation of the various products. With 2.0 percent Pd, the supported dendritic CeZrZn catalyst exhibits the highest catalytic performance (29.1% conversion and 40.6% MeOH selectivity). Comprehensive analysis revealed in this research not only identified effective catalysts with high activity for a variety of applications, but also established a link between catalytic performance and the material's nature. These discoveries may also aid the researcher in the near future in resolving global environmental problems.

Indiana University-Purdue University Indianapolis (IUPUI) / Based on plane wave DFT calculation, we carried out micro level investigation of hydrogen storage in nanoporous silicon (npSi). One quarter of a hexagonal pore with Palladium catalyst placed at the surface has been studied for hydrogen dissociation, spillover, bond hopping, and diffusion for both single catalyst atom and small catalyst cluster consisting of multiple catalyst atoms. All the DFT computations were done in one of the biggest research supercomputer facilities of the world, Big Red II. We opted ABINIT, an open source DFT tool for our computations. Our calculation revealed low dissociation, spillover, and bond hoping energy barrier. The energy required to be provided from external sources to fully recharge the storage medium from a gaseous source at a completely empty state has also been evaluated. Hydrogen diffusion along the inner surface of the pore as a means of bond hopping and the possibility of quantum tunneling, a low temperature phenomena used to spontaneously go over an otherwise less likely high energy barrier have been studied as well. Using these micro level parameter values evaluated from the DFT study, the performance of any potential hydrogen storage material can be compared to a set of characteristics sought in an efficient storage media. Thus, the micro scale feasibility of this novel npSi material based hydrogen storage technology was studied as a part of a STTR Phase I project.