Low thermal expansion ceramics are defined as ceramic materials with a thermal expansion coefficient below 2.0×10^-6 ℃^-1. Compared to other conventional ceramics, these materials exhibit exceptional resistance to high temperatures and thermal shock, maintaining stability in complex environments characterized by high temperatures and abrupt temperature changes. They find widespread application in various fields, including refractory materials, catalyst carriers, electronic devices, and aerospace. This article reviews the classification, preparation methods, and application domains of low thermal expansion ceramics, and examines the research advancements of several common types such as cordierite, aluminum titanate, NaZr₂(PO₄)₃, and lithium ceramics. Additionally, the article discusses the development trends in this field.

MXenes have received extensive attention from scholars due to their unique layered structure, significant electrical conductivity, and excellent mechanical properties. In addition to their pristine forms, they could also be incorporated with other components for attaining hybrids and nanocomposites, accompanying with amplified functionalities. It has been widely used in lithium batteries, supercapacitors, electromagnetic shielding, tumor therapy, biosensors, photocatalysis, and other fields, and has shown great application potential in energy conversion and storage. The purpose of this article is to encyclopaedically overview the latest progress in synthesis and characterization of MXenes, while their potential applications in energy conversation such as water splitting and solar cells, as well as in energy storage such as Li-ion batteries, supercapacitors, and hydrogen energy will be comprehensively elaborated. Development opportunities and challenges are summarized.