http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Arrangement of Block Copolymer Microdomains Confined inside Hemispherical Cavities
Bae, Dusik,Jeon, Gumhye,Jinnai, Hiroshi,Huh, June,Kim, Jin Kon American Chemical Society 2013 Macromolecules Vol.46 No.13
<P>We investigated, via scanning and transmission electron microscopy, the arrangement of the microdomains of symmetric polystyrene-<I>block</I>-poly(methyl methacrylate) copolymer (PS-<I>b</I>-PMMA) confined in hemispherical cavities. The hemispherical cavities were prepared by using anodic aluminum oxide (AAO) template, where the inner surface of the cavities was modified by thin brush layers of PS, PMMA, and PS-<I>ran</I>-PMMA copolymer. When the inner surface of the cavity is strongly selective to PS chains, concentric rings consisting of PS and PMMA microdomains are formed, replicating the confined geometry of hemisphere. However, as the selectivity of a brush to PS chains becomes weaker, various interesting morphologies are formed that have not been reported in the literature. The experimentally observed microdomain arrangement confined inside the hemispherical cavities was compared with the simulation results based on the dynamic Metropolis Monte Carlo method.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/mamobx/2013/mamobx.2013.46.issue-13/ma4009324/production/images/medium/ma-2013-009324_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ma4009324'>ACS Electronic Supporting Info</A></P>
Kim, Joo-Hyun,Kim, Min,Jinnai, Hiroshi,Shin, Tae Joo,Kim, Haena,Park, Jong Hwan,Jo, Sae Byeok,Cho, Kilwon American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.8
<P>The influence of micrometer-scale poly(3-hexylthiophene) (P3HT) nanowires (NWs) and P3HT nanocrystals (NCs) on the photocurrent generation in photoactive layers having various thickness values was investigated. Self-organizing P3HT NWs were fabricated using a marginal solvent. Transmission electron microtomography was used to characterize the vertical and horizontal crystalline morphologies of the NWs and their intergrain percolation networks in the active layers. The interpenetrating P3HT NWs promoted charge transport, as demonstrated by the enhanced percolation probability and the reduction in bimolecular recombination. The photovoltaic performances were enhanced as the photoactive layer thickness increased because internal quantum efficiencies of the solar devices prepared with active layers having NWs were maintained with varying thicknesses, suggesting that the conversion of absorbed photons into a photocurrent proceeded efficiently. By contrast, the photovoltaic performances of an NC-only photoactive layer were reduced by the increase in thickness due to its poorly developed percolation pathways. The incorporation of P3HT NWs into the P3HT:indene-C<SUB>60</SUB> bisadduct photoactive layers yielded a device power conversion efficiency (PCE) of 5.42%, and the photocurrent did not decrease significantly up to a thickness of 600 nm, resulting in a PCE of 3.75%, 70% of the maximum PCE of 5.42%.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-8/am501358k/production/images/medium/am-2014-01358k_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am501358k'>ACS Electronic Supporting Info</A></P>