Versatile metal-free carbon materials from ZIF-8: Insights into construction strategies, properties, applications and structure-activity relationships

Abstract

Exploring efficient functional materials for environmental remediation and energy storage and conversion is in the spotlight due to the overuse of traditional fossil fuels and the severe pollution of the environment. Metal-free carbon materials (MFCMs) with abundant sources, high electrical conductivity, surface functionalities and environmental compatibility represent promising candidates for environmental remediation, energy storage and conversion. Compared with conventional MFCMs, metal-organic framework (MOF)-derived MFCMs inherit the properties and advantages (tunable module, intrinsic diversity and interesting activities) of their parent materials, becoming the optimal multifunctional materials in recent years. Especially, zeolitic imidazolate framework-8 (ZIF-8)-derived MFCMs with richer pore structures and stronger electron transfer capabilities have gained much attention. Previously, the synthesis and applications of ZIF-8-derived MFCMs were only slightly covered in some MOF-related reviews, and there is still a lack of targeted summaries and discussions for them. To this end, the present work starts with an introduction of strategies for designing ZIF-8-derived MFCMs from the perspective of different precursors followed by a discussion of significant advantages obtained from ZIF-8-derived MFCMs. Subsequently, based on density-functional theory (DFT), the structures and related reaction mechanisms of ZIF-8-derived MFCMs are discussed thoroughly in order to construct structure-activity relationships. On this basis, recent advances in their environmental and energy applications are outlined, then economic and technical feasibility analyses are conducted to lay the foundation for their commercialization. Finally, valuable insights are provided into the current challenges and future prospects of ZIF-8-derived MFCMs.