Elena Tresso

The advent of copper‐based electrocatalysts has significantly advanced the electrochemical conversion of CO ₂ into valuable multicarbon fuels and chemicals. Among various synthesis methods, vapor deposition techniques offer a facile and innovative approach to produce catalysts with high conformance and precise control of morphology, thickness, and composition. This article provides a review of the application of the main vapor deposition techniques for the development of copper‐based catalysts and electrodes for tuned CO ₂ reduction reaction (CO2RR). The first part introduces the CO2RR principles, electrolyzer types and components, and Cu electrocatalysts, highlighting their critical role in efficient CO2RR. Then, the principles of physical vapor deposition (PVD), chemical vapor deposition (CVD), and atomic layer deposition (ALD) are introduced, including the process variations and comparative advantages. This review highlights the most promising results obtained with Cu‐based catalysts and electrodes for CO2RR via vapor deposition, with a particular focus on monometallic, bimetallic, single‐atom, and modified Cu catalysts. The review concludes with our perspectives on applying vapor deposition techniques for advanced catalyst preparation. We emphasize that combining these techniques offers unique opportunities to fine tune the material properties at the nanoscale, thereby optimizing active sites for improved CO ₂ conversion selectivity and activity.

In this study, a novel functionalized graphene oxide (fGO) is proposed for application in water desalination. The fGO is obtained with a simple and scalable method. Pristine GO is functionalized with (2‐(acryloyloxy)ethyl)trimethylammonium through a two‐step functionalization. Then, it is mixed with activated carbon and coated onto a metallic current collector. Material characterization techniques such as electron microscopy, thermal analyses, and infrared spectroscopy are employed to study the physical and chemical structures of the proposed materials. This process provides a porous electrode useful for capacitive deionization (CDI). The desalination performance is compared to the performance of bare activated carbons, showing a remarkable improvement. The final device reaches a value of around 17 mg g^‐1 of salt removal, with a charge efficiency of 98%. The findings from this study lay the groundwork for future research, contributing in increasing the existing knowledge on materials for CDI.

The aim of this paper is to shed light on the application of graphene oxide (GO) membranes for the selective removal of benzene, toluene, and xylene (BTX) from wastewater. These molecules are present in traces in the water produced from oil and gas plants and are treated now with complex filtration systems. GO membranes are obtained by a simple, fast, and scalable method. The focus of this work is to prove the possibility of employing GO membranes for the filtration of organic contaminants present in traces in oil and gas wastewater, which has never been reported. The stability of GO membranes is analyzed in water solutions with different pH and salinity. Details of the membrane preparation are provided, resulting in a crucial step to achieve a good filtration performance. Material characterization techniques such as electron microscopy, x-ray diffraction, and infrared spectroscopy are employed to study the physical and chemical structure of GO membranes, while gas chromatography, UV-visible spectroscopy, and gravimetric techniques allow the quantification of their filtration performance. An impressive rejection of about 90% was achieved for 1 ppm of toluene and other pollutants in water, demonstrating the excellent performance of GO membranes in the oil and gas field.

A simple, low cost, and “green” method of hydrothermal synthesis, based on the addition of l-ascorbic acid (l-AA) as a reducing agent, is presented in order to obtain reduced graphene oxide (rGO) and hybrid rGO-MoO₂ aerogels for the fabrication of supercapacitors. The resulting high degree of chemical reduction of graphene oxide (GO), confirmed by X-Ray Photoelectron Spectroscopy (XPS) analysis, is shown to produce a better electrical double layer (EDL) capacitance, as shown by cyclic voltammetric (CV) measurements. Moreover, a good reduction yield of the carbonaceous 3D-scaffold seems to be achievable even when the precursor of molybdenum oxide is added to the pristine slurry in order to get the hybrid rGO-MoO₂ compound. The pseudocapacitance contribution from the resulting embedded MoO₂ microstructures, was then studied by means of CV and electrochemical impedance spectroscopy (EIS). The oxidation state of the molybdenum in the MoO₂ particles embedded in the rGO aerogel was deeply studied by means of XPS analysis and valuable information on the electrochemical behavior, according to the involved redox reactions, was obtained. Finally, the increased stability of the aerogels prepared with l-AA, after charge-discharge cycling, was demonstrated and confirmed by means of Field Emission Scanning Electron Microscopy (FESEM) characterization.

Nanostructured materials possess unique physical-chemical characteristics and have attracted much attention, among others, in the field of energy conversion and storage devices, for the possibility to exploit both their bulk and surface properties, enabling enhanced electron and ion transport, fast diffusion of electrolytes, and consequently high efficiency in the electrochemical processes. In particular, titanium dioxide received great attention, both in the form of amorphous or crystalline material for these applications, due to the large variety of nanostructures in which it can be obtained. In this paper, a comparison of the performance of titanium dioxide prepared through the oxidation of Ti foils in hydrogen peroxide is reported. In particular, two thermal treatments have been compared. One, at 150 °C in Ar, which serves to remove the residual hydrogen peroxide, and the second, at 450 °C in air. The material, after the treatment at 150 °C, results to be not stoichiometric and amorphous, while the treatment at 450 °C provide TiO₂ in the anatase form. It turns out that not-stoichiometric TiO₂ results to be a highly stable material, being a promising candidate for applications as high power Li-ion batteries, while the anatase TiO₂ shows lower cyclability, but it is still promising for energy-storage devices.

Owing to their exceptional electrochemical stability, ionic liquids (ILs) are highly promising electrolytes for high voltage electrochemical double layer capacitors (EDLCs). However, these molten salts often suffer from high viscosity and low conductivity, strongly affecting their application at room temperature. In this work the potential role of N‐butyl‐N‐methyl‐pyrrolidinium 4,5‐dicyano‐2‐(trifluoromethyl) imidazole (Pyr₁₄TDI) as electrolyte component is evaluated for the first time. Although it is classified as an IL, its melting point at 48 °C hinders the use of the pure IL as solvent‐free electrolyte at medium‐to‐low temperatures. For this reason, mixtures with propylene carbonate (PC) are investigated to widen its temperature operation range (−30 to 60 °C). Different Pyr₁₄TDI:PC ratios are investigated, from diluted solution (1 : 3 w/w) to solvent‐in‐salt (3 : 1 w/w). The properties of such electrolytes are determined in terms of viscosity, density, flash point, ionic conductivity, and electrochemical performance in EDLC. By proper electrode balancing, a maximum cell voltage of 3.3 V is achieved in case of PC:Pyr₁₄TDI (1 : 3). However, despite the voltage limitation to 3 V, the highest specific energy and power values are obtained with the most diluted solution (3 : 1).