Non-firing Synthesis for Oxides: From Natural to Synthetic Forms with Energy-Efficient and Sustainable Processes

Abstract

Non-firing functional oxide materials are attracting significant interest due to their suitability for a wide range of applications, particularly in thermal, electrical, and architectural fields. These materials, which range from natural to synthetic forms, offer a diverse range of properties. While oxides are generally known for their high mechanical strength, temperature resistance, and cost-effectiveness, traditional oxide processing often requires energy-intensive and environmentally unfriendly high-temperature sintering. Therefore, the investigation of energy-efficient non-firing mechanisms for oxides is not only beneficial but crucial. This paper reviews the advancements in non-firing mechanisms, with a focus on material selection, synthesis processes, and potential applications. Special attention is given to non-firing forms such as silica-based and geopolymer materials, which are prepared using low-energy acid-base reactions with either natural or synthetic silica-alumina sources. The review also encapsulates the challenges and solutions associated with these sustainable, non-firing oxide materials.

Graphical Abstract