Application of halloysite nanotubes for batteries and supercapacitors

The advancement of novel materials for energy storage devices is a crucial conceptualization to address the limitation in the application of energy storage devices. Layered nano clay and its derivatives exhibit diverse crystal structures and surface functionalities, which can be modified through chemical, electrochemical, or physical means to yield innovative materials. Halloysite nanotubes (HNTs), a widely available aluminosilicate layered nano clay, possess a range of distinctive properties including a core-shell structure, high specific surface area, and different surface charged properties. Consequently, HNTs exhibit immense potential for utilization in energy storage equipment, such as batteries and supercapacitors. This paper initially presents the composite mechanism of HNTs based on their structural characteristics. It subsequently provides an overview of the research advancements in HNTs-related composite materials, focusing on electrode materials, electrolytes, and separators. The paper further summarizes the knowledge of HNTs-derived carbon materials, transition-metal materials, and polymer composite electrodes. Additionally, it analyzes the challenges encountered by HNTs in lithium-ion batteries (LIBs) and supercapacitors (SCs). The ultimate objective is to facilitate the progress of HNTs in the realm of electrochemical energy storage.