Excitonic effect in MOFs-mediated photocatalysis: Phenomenon, characterization techniques and regulation strategies

[Display omitted] •Excitonic effect in MOFs-mediated photocatalysis is reviewed for the first time.•Formation of reactive species via charge transfer and energy transfer are discussed.•The progress in characterization & modification strategies for MOFs is summarized.•Current challenges in MOFs-mediated photocatalysis are put forward.•Future perspectives for the further investigation on excitonic effect are proposed. Metal-organic frameworks (MOFs)-mediated photocatalysis provides a promising solution to energy shortage and environmental pollution. In the past few years, a large number of modification strategies for improving the photocatalytic performance of MOFs have been developed. Correspondingly, many profound photocatalytic mechanisms, such as the excitonic effect, have been proposed. The newly revealed excitonic effect plays a significant role in the formation of reactive species via either charge transfer or energy transfer. Thus, an up-to-date understanding of MOFs-mediated photocatalysis with the excitonic effect is highly needed. In this work, the excitonic effects in charge transfer and energy transfer processes were critically reviewed for the first time, covering a summary of common techniques for characterizing excitonic effect and mainstream strategies for regulating excitonic behaviors. In addition, the current challenges and future perspectives of MOFs-mediated photocatalysis for energy conversion and environmental remediation were discussed.