Shailza Saini

Cerium oxide (CeO2) is a widely used catalyst support in electrochemical and catalytic applications due to its ability to form oxygen vacancies and strong metal-support interactions. However, conventionally prepared CeO2 catalysts often suffer from deactivation due to sintering and poisoning. Incorporating dopants such as gadolinium (Gd) and zirconium (Zr) into its lattice improves oxygen ion mobility, thermal stability, and resistance to poisoning. Platinum (Pt) is a commonly used catalyst for the oxygen reduction reaction in microbial fuel cells for real-time biochemical oxygen demand monitoring. However, its high cost, scarcity, and susceptibility to fouling and poisoning limit implementation in wastewater treatment plants. This study employs the exsolution method to investigate the formation of Pt nanoparticles from undoped, Zr-, and Gd-doped CeO2 matrices. It is shown that the Gd-doped matrix exhibits the optimal particle characteristics, while electrochemical evaluation in the microbial fuel cells also reveals that it outperforms the other studied materials, in terms of sensitivity and stability. By integrating exsolution with dopant engineering, in an innovative approach, we lower costs, maintain performance, and enhance the operational stability of the cathode material, paving the way for cost-effective and sustainable applications in biosensing but also other catalytic applications of interest.

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.

Air-cathode microbial fuel cells (MFCs) have emerged as efficient, self-powered biosensors for rapid and continuous monitoring of biochemical oxygen demand (BOD) in municipal wastewater. The oxygen reduction reaction (ORR) at the cathode is critical to the performance of MFCs. However, platinum (Pt), the traditional catalyst for ORR, faces limitations due to its high cost, limited availability, and concerns about long-term operational stability. By using exsolution, this study focuses on reducing the operational costs of MFC-based biosensors by decreasing the noble metal content in the air-cathode while preserving the performance for BOD monitoring of complex synthetic urban wastewater. Additionally, the study explores the efficacy of novel exsolved Rh-titanate perovskite (La0.43Ca0.37Ti0.94Rh0.06O3-δ, LCT-Rh) as an alternative to conventional Pt/C to enhance operational stability. Results indicate that the optimal noble catalyst concentration for the MFC used in this study was 0.06 mgPGM cm⁻², approximately five times lower than typical concentrations cited in the literature, while still maintaining comparable efficacy. Performance comparisons between air-cathode MFCs using LCT-Rh and Pt/C showed similar outcomes, with a dynamic range of 26–363 mg L⁻¹ COD and sensitivity of 0.85 mA L⁻¹ m⁻² mgCOD⁻¹ for Rh-MFCs and 0.81 mA L⁻¹ m⁻² mgCOD⁻¹ for Pt-MFCs. Accuracy ranged from 90 % to 99 % for Rh-MFCs and from 58 % to 97 % for Pt-MFCs. Cyclic voltammetry and polarization curve analyses demonstrated that LCT-Rh maintained more stable catalytic activity after 35 days of continuous flow operation. This investigation introduces exsolved Rh-titanate perovskite as a viable catalyst for ORR in MFC-based biosensors.

The raw data is the experimental data of the paper 'Exsolution of Pt Nanoparticles from Mixed Zr/Gd-CeO2 Oxides for Microbial Fuel Cell-Based Biosensors' which is accepted in the Small Science Journal. The format includes pdf ,txt, png, tiff and xls. 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 atomic % Ir-BaTiO3, which showed 82% and 86% conversion of CO(2 )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/g(sample) detected for the exsolved system. These findings highlight the possibility of achieving in a single step the mutual interaction of the parameters enhancing the catalytic efficiency, leading to a promising pathway for the design of catalysts for reforming reactions.

An intimate Cu–ZnO interface that allows for the conversion of CO2 to methanol even at atmospheric pressures was produced using the exsolution method. Detailed characterization and operando IR spectroscopy were employed to deconvolute the materials' properties that allow for this to happen.

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.

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.