Rankin Christopher, Chou Chun-Han, Conklin David, Bonnell Dawn A
Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
ACS Nano. 2007 Oct;1(3):234-8. doi: 10.1021/nn7000728.
Molecular polarization of ferroelectric poly(vinylidene fluoride) (PVDF) is manipulated at the nanometer scale in order to influence the local electronic structure and reactivity at the surface. A direct current voltage, applied through a conductive scanning probe tip, is used to pattern ferroelectric domains in a PVDF thin film, and the polarization direction of these domains influences the kinetics of electron exchange at the surface. By means of a surface photoreduction reaction, which occurs in a metal ion solution under ultraviolet irradiation, metal nanoparticles are deposited in predetermined configurations on polymer surfaces. The photoexcited carriers are generated from defect states within the energy gap of the material, and these gap states are found not only at the interface but throughout the bulk polymer. This represents the first demonstration of ferroelectric nanolithography on an organic substrate and opens the door to applications in organic electronics.
为了影响铁电聚偏二氟乙烯(PVDF)表面的局部电子结构和反应活性,在纳米尺度上对其分子极化进行调控。通过导电扫描探针尖端施加直流电压,用于在PVDF薄膜中对铁电畴进行图案化,这些畴的极化方向会影响表面电子交换的动力学。借助在金属离子溶液中紫外光照射下发生的表面光还原反应,金属纳米颗粒以预定构型沉积在聚合物表面。光激发载流子由材料能隙内的缺陷态产生,这些能隙态不仅出现在界面处,还存在于整个聚合物本体中。这是在有机衬底上进行铁电纳米光刻的首次证明,为有机电子学的应用打开了大门。