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Controlling the morphological, structural, and optical properties of one-dimensional PCDTBT nanotubes by template wetting.

Bakar NA, Supangat A, Sulaiman K - Nanoscale Res Lett (2014)

Bottom Line: In this study, the synthesis of poly [N-9'-heptadecanyl-2, 7-carbazole-alt-5, 5-(4', 7'-di-2-thienyl-2', 1', 3'-benzothiadiazole)] (PCDTBT) nanotubes via a templating method is reported.PCDTBT nanotubes were successfully grown by immersing the porous alumina template into 15 mg/ml of solution concentration for 2- and 24-h periods and annealed at 50°C.Nanotubes that are formed between 2 and 24 h of infiltration show enhancement in absorption, photoluminescence, and shift in Raman peak if compared to their thin films.

View Article: PubMed Central - HTML - PubMed

Affiliation: Low Dimensional Materials Research Centre, Department of Physics, University of Malaya, Kuala Lumpur 50603, Malaysia.

ABSTRACT
In this study, the synthesis of poly [N-9'-heptadecanyl-2, 7-carbazole-alt-5, 5-(4', 7'-di-2-thienyl-2', 1', 3'-benzothiadiazole)] (PCDTBT) nanotubes via a templating method is reported. PCDTBT nanotubes were successfully grown by immersing the porous alumina template into 15 mg/ml of solution concentration for 2- and 24-h periods and annealed at 50°C. Changes in morphological and optical properties between nanotubes of different infiltration times (2 and 24 h) as well as its thin films are observed. The longer infiltration time of 24 h produced nanotubes with enhanced morphological, structural, and optical properties. Nanotubes that are formed between 2 and 24 h of infiltration show enhancement in absorption, photoluminescence, and shift in Raman peak if compared to their thin films.

No MeSH data available.


Related in: MedlinePlus

Photoluminescence spectra. Comparison of PL spectra of (a) PCDTBT nanotubes of 2 h of immersion time and thin film, (b) PCDTBT nanotubes of 24 h of immersion time and thin film, and (c) PCDTBT nanotubes of 2 and 24 h of immersion time.
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Figure 5: Photoluminescence spectra. Comparison of PL spectra of (a) PCDTBT nanotubes of 2 h of immersion time and thin film, (b) PCDTBT nanotubes of 24 h of immersion time and thin film, and (c) PCDTBT nanotubes of 2 and 24 h of immersion time.

Mentions: The UV-vis absorption and photoluminescence (PL) spectra of PCDTBT nanotubes prepared between 2 and 24 h of immersion time are shown in Figures 4 and5, respectively. The UV-vis absorption spectra clearly show the two absorption bands at UV and visible region which represent the donor carbazole (Cz) and acceptor dithienylbenzothiadiazole (DTBT), respectively[4]. Wider band absorption at longer wavelength could be observed for both the nanotubes prepared between 2 and 24 h of immersion time if compared to their thin films. This is an indication of better optical properties garnered by PCDTBT nanotubes in terms of light absorption. The main absorption peak of PCDTBT nanotubes is located at approximately 627 and 640 nm for 2 and 24 h of immersion time, respectively, and possesses a significant red-shift of about 75 and 88 nm as compared to their thin films. This could be attributed to the highly aggregated configuration in the polymer chain system of PCDTBT nanotubes. In the highly aggregated configuration, the polymer chains may align themselves and increase the conjugation length[18]. Aligned polymer chains provide a route for the efficient charge transfer (π to π*) between the conjugated main chains (DTBT) and carbazole (Cz) units. Modification in the molecular structure of nanotubes such as aggregation and chain alignment may improve the optical properties by enhancing the interchain and intrachain interaction. Dissimilar morphological distributions of the nanotubes give the distinct optical properties as indicated from the red-shift of about 13 nm by the nanotubes prepared for 24 h of immersion time. This is unlikely to happen to the PCDTBT nanotubes synthesized for 2 h of immersion time.


Controlling the morphological, structural, and optical properties of one-dimensional PCDTBT nanotubes by template wetting.

Bakar NA, Supangat A, Sulaiman K - Nanoscale Res Lett (2014)

Photoluminescence spectra. Comparison of PL spectra of (a) PCDTBT nanotubes of 2 h of immersion time and thin film, (b) PCDTBT nanotubes of 24 h of immersion time and thin film, and (c) PCDTBT nanotubes of 2 and 24 h of immersion time.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4225451&req=5

Figure 5: Photoluminescence spectra. Comparison of PL spectra of (a) PCDTBT nanotubes of 2 h of immersion time and thin film, (b) PCDTBT nanotubes of 24 h of immersion time and thin film, and (c) PCDTBT nanotubes of 2 and 24 h of immersion time.
Mentions: The UV-vis absorption and photoluminescence (PL) spectra of PCDTBT nanotubes prepared between 2 and 24 h of immersion time are shown in Figures 4 and5, respectively. The UV-vis absorption spectra clearly show the two absorption bands at UV and visible region which represent the donor carbazole (Cz) and acceptor dithienylbenzothiadiazole (DTBT), respectively[4]. Wider band absorption at longer wavelength could be observed for both the nanotubes prepared between 2 and 24 h of immersion time if compared to their thin films. This is an indication of better optical properties garnered by PCDTBT nanotubes in terms of light absorption. The main absorption peak of PCDTBT nanotubes is located at approximately 627 and 640 nm for 2 and 24 h of immersion time, respectively, and possesses a significant red-shift of about 75 and 88 nm as compared to their thin films. This could be attributed to the highly aggregated configuration in the polymer chain system of PCDTBT nanotubes. In the highly aggregated configuration, the polymer chains may align themselves and increase the conjugation length[18]. Aligned polymer chains provide a route for the efficient charge transfer (π to π*) between the conjugated main chains (DTBT) and carbazole (Cz) units. Modification in the molecular structure of nanotubes such as aggregation and chain alignment may improve the optical properties by enhancing the interchain and intrachain interaction. Dissimilar morphological distributions of the nanotubes give the distinct optical properties as indicated from the red-shift of about 13 nm by the nanotubes prepared for 24 h of immersion time. This is unlikely to happen to the PCDTBT nanotubes synthesized for 2 h of immersion time.

Bottom Line: In this study, the synthesis of poly [N-9'-heptadecanyl-2, 7-carbazole-alt-5, 5-(4', 7'-di-2-thienyl-2', 1', 3'-benzothiadiazole)] (PCDTBT) nanotubes via a templating method is reported.PCDTBT nanotubes were successfully grown by immersing the porous alumina template into 15 mg/ml of solution concentration for 2- and 24-h periods and annealed at 50°C.Nanotubes that are formed between 2 and 24 h of infiltration show enhancement in absorption, photoluminescence, and shift in Raman peak if compared to their thin films.

View Article: PubMed Central - HTML - PubMed

Affiliation: Low Dimensional Materials Research Centre, Department of Physics, University of Malaya, Kuala Lumpur 50603, Malaysia.

ABSTRACT
In this study, the synthesis of poly [N-9'-heptadecanyl-2, 7-carbazole-alt-5, 5-(4', 7'-di-2-thienyl-2', 1', 3'-benzothiadiazole)] (PCDTBT) nanotubes via a templating method is reported. PCDTBT nanotubes were successfully grown by immersing the porous alumina template into 15 mg/ml of solution concentration for 2- and 24-h periods and annealed at 50°C. Changes in morphological and optical properties between nanotubes of different infiltration times (2 and 24 h) as well as its thin films are observed. The longer infiltration time of 24 h produced nanotubes with enhanced morphological, structural, and optical properties. Nanotubes that are formed between 2 and 24 h of infiltration show enhancement in absorption, photoluminescence, and shift in Raman peak if compared to their thin films.

No MeSH data available.


Related in: MedlinePlus