Tunable in Situ Stress and Spontaneous Microwrinkling of Multiscale Heterostructures
Utilizing and tuning internal stress is a powerful strategy to engineer structures and properties of two-dimensional materials and their assemblies. Stress change is commonly induced by either external stress from the substrate, physical changes, or intrinsic surface stress but control of it is limited by interfacial reconstructions, complex processing, or small material scale. Here, we developed an in situ stress method by simultaneously exploiting reaction-induced stress in 2D-based multiscale materials. Molecular-scale intercalating reactions form nanocrystals on the host sheets and make internal stress tunable. Reduced graphene oxide (rGO)-graphitic carbon nitride was obtained with self-organized microwrinkles, using newly formed g-C3N4 as interlayers and thermochemical stress as the driving force. The heterostructures obtained range from macronetwork to few-layer and different 2D materials including MoO3, and BN sheets are proven applicable to this stress-morphing method. This work suggests that in situ stress induced during reactions by changes of bonds and materials is effective of stress/strain control and functional structure fabrication.