Shailza Saini
Academic and research departments
School of Chemistry and Chemical Engineering, Faculty of Engineering and Physical Sciences.About
My research project
Highly efficient exsolution catalysts for CO2 utilisationEU aims to decrease its greenhouse gas emissions by 80-95% by 2050. At the moment the energy sector is responsible for ~75% of these emissions and our energy demands only keep increasing. Exsolution is an approach to producing nanoparticles with unique metal-support interaction, also displaying enhanced activity and stability. In this project we will prepare novel nano-structured catalysts using exsolution. We explore different nanostructure configurations and their effect on activity and selectivity when converting CO2 to synthetic fuels.
Supervisors
EU aims to decrease its greenhouse gas emissions by 80-95% by 2050. At the moment the energy sector is responsible for ~75% of these emissions and our energy demands only keep increasing. Exsolution is an approach to producing nanoparticles with unique metal-support interaction, also displaying enhanced activity and stability. In this project we will prepare novel nano-structured catalysts using exsolution. We explore different nanostructure configurations and their effect on activity and selectivity when converting CO2 to synthetic fuels.
University roles and responsibilities
- PGR Chemical engineering Representative
Affiliations and memberships
Publications
The raw data is the experimental data of the paper 'Exsolved Cu-ZnO Interfaces for methanol Production from CO2 at atmospheric pressure' which is accepted in the Journal of Materials Chemistry A. All the listed files include the catalytic data and material characterisation including SEM, TEM,XRD and XPS. The format includes pdf ,txt, png, tiff and xls. The file format is open access format.
This includes the experimental data for the reverse water gas shift reaction. The data uploaded includes XRD, SEM, XPS and catalytic results for the materials used in the reaction. All the data is open access and is in .txt and .jpg format which can be accessible by any text editor.
The raw data is the experimental data of the paper 'Enhanced Stability of Iridium Nanocatalysts via Exsolution for the CO2 Reforming of Methane' which is accepted in the Journal ACS Applied Nano Materials. All the listed files include the catalytic data and material characterisation including SEM, TEM and XPS. The figures are denoted as Fig Xy-w, where X is the number of the figure, y is the part of the figure and w is explanation of each figure. The format includes txt, pdf, tiff and png file. The file format is open access format. The reforming reactions of greenhouse gases require catalysts with high reactivity, coking resistance, and structural stability for efficient and durable use. Among the possible strategies, exsolution has been shown to demonstrate the requirements needed to produce appropriate catalysts for the dry reforming of methane, the conversion of which strongly depends on the choice of active species, its interaction with the support, and the catalyst size and dispersion properties. Here, we exploit the exsolution approach, known to produce stable and highly active nanoparticle-supported catalysts, to develop iridium nanoparticle-decorated perovskites and apply them as catalysts for the dry reforming of methane. By studying the effect of several parameters, we tune the degree of exsolution, and consequently the catalytic activity, thereby identifying the most efficient sample - 0.5 at% Ir-BaTiO3, which showed 82% and 86% conversion of CO2 and CH4, respectively. By comparison with standard impregnated catalysts (e.g., Ir/Al2O3), we benchmark the activity and stability of our exsolved systems. We find almost identical conversion and syngas rates of formation, but observe no carbon deposition for the exsolved samples after catalytic testing; such deposition was significant for the traditionally prepared impregnated Ir/Al2O3, with almost 30 mgC/gsample measured, compared to 0 mgC/gsample detected for the exsolved system. These findings highlight the possibility of achieving in a single step the mutual interaction of the parameters enhancing catalytic efficiency, leading to a promising pathway for the design of catalysts for reforming reactions.
The reverse water-gas shift reaction (rWGS) is of particular interest as it is the first step to producing high-added-value products from carbon dioxide (CO2) and renewable hydrogen (H2), such as synthetic fuels or other chemical building blocks (e.g. methanol) through a modified Fischer-Tropsch process. However, side reactions and material deactivation issues, depending on the conditions used, still make it challenging. Efforts have been put into developing and improving scalable catalysts that can deliver high selectivity while at the same time being able to avoid deactivation through high temperature sintering and/or carbon deposition. Here we design a set of perovskite ferrites specifically tailored to the hydrogenation of CO2 via the reverse water-gas shift reaction. We tailor the oxygen vacancies, proven to play a major role in the process, by partially substituting the primary A-site element (Barium, Ba) with Praseodymium (Pr) and Samarium (Sm), and also dope the B-site with a small amount of Nickel (Ni). We also take advantage of the exsolution process and manage to produce highly selective Fe-Ni alloys that suppress the formation of any by-products, leading to up to 100% CO selectivity. •Partial A-site substitution with Pr, Sm, affects oxygen vacancies formation and microstructure.•Incorporation of Ni on the B-site affects the morphology and stability of the perovskites and induces exsolution.•Combination of Fe-Ni alloy formation and pre-treatment optimization leads up to 100% selectivity to CO.