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The novel and well-defined supramolecular amphiphilic star-branched copolymer poly((caprolactone)-star-(poly(2-N,N-dimethylamino)ethylmethacrylate) 7 (PCL-(PDMAEMA) 7 ) with a porphyrin core was prepared via the combination of ring-opening polymerization (ROP), atom transfer radical polymerization (ATRP), and supramolecular host-guest inclusion complexation. After reaction of PDMAEMA with excess 1,3-propane sultone, the quaternized star-PCL-(PDMAEMA) 7 was obtained. The amphiphilic star-PCL-(PDMAEMA) 7 and quaternized star-PCL-(PDMAEMA) 7 can selfassemble into spherical nano-micelles by directly dissolving in water. This thermoresponsive micelles solution shows a transition from a lower critical solution temperature (LCST) of star-PCL-(PDMAEMA) 7 to an upper critical solution temperature (UCST) of quaternized star-PCL-(PDMAEMA) 7 , indicating that the LCST-UCST transition of micellar solutions can be accomplished by the transition of PDMAEMA to quaternized PDMAEMA. Due to the presence of porphyrin molecules in the micelles core, the micelle solutions present obvious fluorescence and the fluorescent intensity can be adjusted by altering the temperatures. For the star-PCL-(PDMAEMA) 7 micelle solution, the fluorescent intensity decreases with the increase of temperature, while the fluorescent intensity increases with the increase of temperature for the quaternized star-PCL-(PDMAEMA) 7 micelle solution, indicating unique temperature-fluorescence responsive behavior.

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How to predict the bandgap size of graphene antidot lattices (GALs) is a key problem in the field of graphene-based nanoelectronics. Here, we have obtained the universal rules on bandgap opening/closing of GALs with zigzag-edged hexagonal holes (ZH-GALs), as well as the means to control the bandgap size. In the simple case that the electronic property depends on the choice of the supercell, the quantitative relationship between Eg and the density/diameter of antidots is fitted. Turning to complex structures, we reveal that the bandgap opening in ZH-GALs results mainly from the intervalley scattering. In this interpretation, according to their relative position, the antidots can be divided into three categories. A relatively large bandgap appears in ZH-GALs, only when the numbers of the three categories are unequal. This could be explained based on a mechanism similar to diffraction. A formula according to the explanation is provided to estimate the bandgap, which can be used to predict the electronic properties of GALs and guide the design of semiconductor and photoelectronic devices based on GALs.