摘要
用旋徐法实现了多孔硅、多孔氧化铝与聚乙烯咔唑(PVK)的复合,研究了多孔硅/PVK、多孔氧化铝/PVK复合体系的光致发光性能。PL谱的测试发现,多孔硅/PVK复合体系的PL谱同时具有多孔硅和PVK的发射峰。此外,在485 um的位置出现了一个新峰,讨论了这个峰的来源。而多孔氧化铝与PVK复合后,没有产生新的峰。但多孔氧化铝与PVK复合后,由于多孔氧化铝纳米孔的纳米限制效应使PVK的发光峰出现大幅度蓝移。从多孔硅与多孔氧化铝发光机制的不同出发,讨论了多孔硅、多孔氧化铝与PVK复合后产生不同结果的原因。
The purpose of this paper was to investigate the photoluminescence(PL) properties of the composites of
porous silicon(PS)/porous alumina(PA) and poly(N-vinycarbazole) (PVK). The spin coating method was used to
assemble porous silicon (PS)/porous alumina(PA) with polymer (PVK). The photoluminescence properties of the
composites of PS/PA, and PVK were studied. The PL spectra of the composites not only showed the peak that be-
longs to PS/PA but also showed the peak that belongs to PVK. At the same time, in the PL spectrum of PS/PVK,
a new peak was found locating at λ=485 nm. The origin of this peak was discussed. It is possible that this peak
origins from the carriers transferring from porous silicon to PVK. PVK could be viewed as a special surface state of
porous silicon in the composite of porous silicon and PVK. Carriers might be excited in intern of the silicon crystal
and transferring to the surface of PVK. Carriers combined on it and a new emission peak at 485 nm appeared. Fur-
thermore, the location of the peak didn't vary with the quality of PVK. So PVK provided with a stable surface
state. The composite of PA/PVK didn't show any new emission peak. But about 20 nm blue shift of the peak of
PVK was found after composition. It has been reported that the conglomeration of conjugated polymer can result in
the narrowness of energy band (E_g). During the formation of PVK polymer thin film, the conglomeration is in-
evitable. After PVK polymer is coated on porous alumina, the polymer will enter into the pores of porous alumina.
Since the diameter of pores is about 60 ～ 70 nm, the surface area of the polymer increases. Furthermore, nano-pore
structure of porous alumina prevents the PVK polymer from conglomeration. Thus, the conglomeration of PVK in
pores of PVK is less than conventional PVK polymer film. The E_g value of the PVK on porous alumina will become
bigger so that about 20 nm blue shift of PL peak of the composite is observed. Therefore, it is concluded that the
nano-meter effect of porous alumina brings on the blue shift of PL spectrum for PVK. The results in this paper veri-
fied the difference of luminescence mechanism between porous silicon and porous alumina. The carriers of porous
silicon are excited in the intern of silicon crystal and combined on the surface of the surface. So the carriers of
porous silicon could transfer to PVK and a new PL peak appeared. However, porous alumina owns fixed lumines-
cence center. Its carriers couldn't transfer to other places. And it is impossible for the composite of porous alumina
and PVK to show a new PL peak that doesn't belong to not only porous silicon but PVK.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2004年第2期178-182,共5页
Chinese Journal of Luminescence
基金
国家杰出青年基金(60225010)
