4.4 Effect of conducting substrate: ZIF-8 is non-conducting, which could lead to sample charging and heating in a TEM experiment. Conducting substrates such as single-layer graphene can be used to reduce the effect of charging. A graphene substrate or a graphene encapsulation can lower the electronic excitation generated by the interaction of the incident electrons with the materials, which reduces electron beam damage . We also used holey carbon , and single-layer graphene substrate to investigate the effect of the substrate material on the loss in crystallinity of ZIF-8. No significant effect of using graphene substrate has been observed in our experiments. The probable reason could be a minimal adhesion between the ZIF-8 and the graphene substrate .