The physical properties of polymers strongly depend on the molecular or supermolecular order and orientation. Here we demonstrate the preferential orientation of lamellar crystals and the enhancement of ferro/piezoelectric properties in individual poly-(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) nanowires fabricated from anodic alumina oxide (AAO) templates. The crystallographic a axis of P(VDF-TrFE) was found to be aligned along the long axis of nanowires due to geometrical confinement and grapho-expitaxial crystals growth. The alignment of lamellar crystals in P(VDF-TrFE) nanowires and enhancement of crystallization translated into improved ferro/piezoelectric properties such as lower coercive field and higher piezoelectric coefficient, testified by piezoresponse force microscopy images and piezoresponse hysteresis loops.

Graphitic carbon nitride (g-C 3 N 4 ) has been widely studied as a fascinating visible-light-response two-dimensional semiconductor photocatalyst. Nevertheless, the quantum yield of g-C 3 N 4 is unsatisfactory due to the insufficient surface reactive sites and slow charge migration efficiency caused by grievous agglomeration and large grain size. Herein this obstacle is overcome through a facile eco-friendly strategy based on effects from a bubble template and nonmetal heteroatom doping of g-C 3 N 4 . This treatment not only restricts the agglomeration but also creates more surface active sites for reaction and more porous channels for charge carrier transfer. Well-amended g-C 3 N 4 nanosheets with porous network and sulfur-doping were prepared with larger specific surface areas and faster electron−hole migration and separation capacity. The modified g-C 3 N 4 nanosheets possessed a H 2 evolution rate 5.3 and 3.8 times enhanced compare with bulk g-C 3 N 4 (BCN) and S-doped g-C 3 N 4 (CNS).

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