The physical grounds for phase-contrast and confocal-reflection microscopies have been used to explain lipid microphase structures by rationalization of the interaction of light with the lipid multilayers. Four types of lipid microphase structuresoily streaks, polygonal arrays, and bubble and striped domainswhich can be characterized by conventional polarizing microscopy were visualized and analyzed in detail by phase-contrast and confocal-reflection microscopies. We find that the images obtained through phase-contrast and confocal-reflection microscopies have even better correlation with lipid alignment models. The complementary nature of polygonal arrays is revealed here by confocal-reflection microscopy. Both confocal-reflection and phase-contrast microscopies were used to characterize the transition processes between striped and bubble domains.

Assembling two-dimensional (2D) nanomaterials into laminar membranes with a subnanometer (subnm) interlayer spacing provides a material platform for studying a range of nanoconfinement effects and exploring the technological applications related to the transport of electrons, ions and molecules. However, the strong tendency for 2D nanomaterials to restack to their bulk crystalline-like structure makes it challenging to control their spacing at the subnm scale. It is thus necessary to understand what nanotextures can be formed at the subnm scale and how they can be engineered experimentally. In this work, with dense reduced graphene oxide membranes as a model system, we combine synchrotronbased X-ray scattering and ionic electrosorption analysis to reveal that their subnanometric stacking can result in a hybrid nanostructure of subnm channels and graphitized clusters. We demonstrate that the ratio of these two structural units, their sizes and connectivity can be engineered by stacking kinetics through the reduction temperature to allow the realization of high-performance compact capacitive energy storage. This work highlights the great complexity of subnm stacking of 2D nanomaterials and provides potential methods to engineer their nanotextures at will.

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