DOI QR코드

DOI QR Code

Characterization of Core/Shell PMMA/CdS Nanoparticles Synthesized by Surfactant-free Emulsion Polymerization

무유화 유화중합에 의해 합성된 Core/shell 형태 PMMA/CdS 나노입자의 특성분석

  • Received : 2012.11.28
  • Accepted : 2012.12.07
  • Published : 2012.12.31

Abstract

Herein, CdS-coated PMMA nanoparticles were prepared by in-situ surfactant-free emulsion copolymerization and subsequent CdS coating process. As-prepared CdS/PMMA hybrid particles had 201.7 nm in diameter. The amount of CdS nanocrystals in the hybrid particles was 10.37 wt% determined by TGA and elemental analysis. The size of CdS crystals was 3.55 nm preferentially grown in (111) plane. UV-vis spectrum of PMMA/CdS nanoparticles showed the significant blue-shift in optical illumination. The reason was found because the synthesized CdS nanocrystals on PMMA particles had a different band gap energy of 2.70 eV which was significantly higher than that of known-value of bulk CdS (2.41 eV) due to a quantum confinement effect.

in-situ 무유화 유화중합 및 후속 CdS 코팅 공정으로 이루어진 방법을 이용하여 CdS로 코팅된 PMMA 나노입자를 제조하고 그 특성을 분석하였다. 합성된 CdS/PMMA 나노입자의 크기는 201.7 nm 였으며, TGA 및 원소 분석 결과 10.37 wt%의 CdS를 함유하고 있었다. PMMA 입자 표면에 코팅된 CdS 나노결정의 크기는 3.55 nm였으며 주로 (111) 결정면으로 성장되었다. UV-vis 분석 결과 blue-shifting 현상이 관찰되었으며, 이는 CdS/PMMA 하이브리드 입자상태에서의 CdS는 벌크 상태의 CdS가 갖는 2.41 eV의 밴드갭 에너지보다 큰 2.70 eV를 갖기 때문에 발생하는 양자구속효과에 의하여 기인하였다.

Keywords

Acknowledgement

Supported by : Ministry of Knowledge Economy (MKE)

References

  1. X. Cheng, Q. Zhao, Y. Yang, S. C. Tjong, and R. Li, J. Colloid Interface Sci., 326, 121 (2008). https://doi.org/10.1016/j.jcis.2008.07.006
  2. A. V. Firth, D. J. Cole-Hamilton, and J. W. Allen, Appl. Phys. Lett., 75, 3120 (1999). https://doi.org/10.1063/1.125250
  3. P. K. Khanna, Synth. React. Inorg., Met.-Org., Nano-Met. Chem., 38, 409 (2008).
  4. Y. Jin, Y. Zhu, X. Yang, H. Jiang, and C. Li, J. Colloid Interface Sci., 301, 130 (2006). https://doi.org/10.1016/j.jcis.2006.04.038
  5. J. Jasieniak, L. Smith, J. Embden, and P. Mulvaney, J. Phys. Chem. C, 113, 19468 (2009). https://doi.org/10.1021/jp906827m
  6. T. Trindade and P. O'Brien, Adv. Mater., 8, 161 (1996). https://doi.org/10.1002/adma.19960080214
  7. H. Yoon, J. Lee, D. W. Park, C. K. Hong, and S. E. Shim, Colloid Polym. Sci., 288, 613 (2010). https://doi.org/10.1007/s00396-009-2174-1
  8. Y. Zhang, L. S. Zha, and S. K. Fu, J. Appl. Polym. Sci., 92, 839 (2004). https://doi.org/10.1002/app.20034
  9. P. Gupta and M. Ramrakhiani, Open Nanosci. J., 3, 15 (2009). https://doi.org/10.2174/1874140100903010015
  10. M. Maleki, M. S. Chamsari, Sh. Mirdamadi, and R. Ghasemzadeh, Semicond. Phys. Quantum Electron. Optoelectron., 10, 30 (2007).
  11. C. Xu, Y. Ni, Z. Zhang, X. Ge, and Q. Ye, Mater. Lett., 57, 3070 (2003). https://doi.org/10.1016/S0167-577X(02)01438-6
  12. D. Wu, X. Ge, Z. Zhang, M. Wang, and S. Zhang, Langmuir, 20, 5192 (2004). https://doi.org/10.1021/la049405d