Fig. 1: Recent developments in norbornadiene for energy storage and a novel concept in this work.

a Designed strategies to promote the efficiency of the MOST process in the NBD-QC system. b The proposed energy profile for the photochemical reaction of the PZDN-PZDQC process. c The synthetic route of PZDN, PZTN, and PZQN. Details of the reaction are provided in the supporting information.