2D Oxide Nanomaterials to Address the Energy Transition and Catalysis

Abstract

2D oxide nanomaterials constitute a broad range of materials, with a wide array of current and potential applications, particularly in the fields of energy storage and catalysis for sustainable energy production. Despite the many similarities in structure, composition, and synthetic methods and uses, the current literature on layered oxides is diverse and disconnected. A number of reviews can be found in the literature, but they are mostly focused on one of the particular subclasses of 2D oxides. This review attempts to bridge the knowledge gap between individual layered oxide types by summarizing recent developments in all important 2D oxide systems including supported ultrathin oxide films, layered clays and double hydroxides, layered perovskites, and novel 2D-zeolite-based materials. Particular attention is paid to the underlying similarities and differences between the various materials, and the subsequent challenges faced by each research community. The potential of layered oxides toward future applications is critically evaluated, especially in the areas of electrocatalysis and photocatalysis, biomass conversion, and fine chemical synthesis. Attention is also paid to corresponding novel 3D materials that can be obtained via sophisticated engineering of 2D oxides.

From 3D to 2D zeolite catalytic materials

“…), characteristic of layered materials, become possible. 9,182 From the synthesis point of view, 2D zeolites have been reviewed recently. Reviews by Roth and coworkers 9,183 and Eliášová and coworkers 31 are recommended for more details.…”

“…Synthesis routes to 2D zeolites described vide supra discussed bottom-up approaches either with conventional or specially designed templates. 8,182 A top-down synthetic protocol is an opposite way, which is applicable for zeolites with anisotropic structures affording the possibility of chemically selective removal of some structural units. This is nicely documented for a series of germanosilicates, originally started with a UTL zeolite followed by UOV and SAZ-1.…”

Chemical engineering role in the use of renewable energy and alternative carbon sources in chemical production

“…Attention is focused on aspects such as light harvesting, charge-separation, band gap broadening and cocatalysis effects. Low dimensional [12] or hollow [79] nanostructures show several potential advantages for photocatalytic materials, such as enhanced light harvesting, potential reduced charge recombination rate by decreasing charge transfer distance and directing separation of charge carriers, and increased accessible surface areas. This is often masked, however, by an increase in defects, acting as centers for charge recombination.…”

“…It is thus necessary to understand where are the bottlenecks, both in terms of fundamental knowledge and technological aspects, limiting the possibility to realize the challenges related to this transition and reach the target to make sustainable and economic these novel technologies. Even if there are increasing papers and reviews in this area, for example on photocatalysts for solar-driven overall water splitting [9] or photoelectrochemical water splitting [10], they are still oriented to analyze only the scientific aspects, including for example the type of materials to use [11,12], rather than to present an holistic view of science and technology aspects. These two aspects should be developed in an integrated manner, rather than sequential, as exemplified from the development of photoelectrocatalytic materials and devices [13].…”

Rapid and Low‐Temperature Salt‐Templated Production of 2D Metal Oxide/Oxychloride/Hydroxide

“…Recently, 2D materials such as graphene, metal oxide, metal carbide, metal dichalcogenides, and pure metal, have played an important role in electronics, sensors, optics, electrocatalysis, and energy storage, owing to the unique atomic thin feature, high specific surface area, and large aspect ratios. Many methods for the preparation of 2D materials have been explored, including liquid phase exfoliation (LPE), mechanical repeated folding and calendaring (RFC), chemical vapor deposition (CVD) or van der Waals epitaxy approach, and salt‐templated or molten salt‐templated method (MSM) .…”