Role of Carbon Dots in Polymer Based Bulk Heterojunction Solar Cells to Achieve High Open Circuit Voltage

  • Rajni SharmaEmail author
  • Firoz Alam
  • Ashok K. Sharma
  • V. Dutta
  • S. K. Dhawan
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 215)


Carbon quantum dots (C-dots) as replacement for conventional fullerenes has been studied and applied to achieve cost-effective (photovoltaic) PV technology. Synthesis of hydrophobic C-dots was done via carbonization of carbohydrates, in the presence of amine. Hydrophobic C-dots along with polymer form homogeneous and clear dispersion in chloroform. It results in the casting of undisrupted film to work as perfect active layer in polymer based bulk heterojunction (BHJ) solar cells. Photoluminescence quenching was done to study photo induced charge transfer in between polymer (as donor) and C-dots (as acceptor). UV-Vis absorbance depicted better utilization of solar spectrum on adding C-dots into polymer. Contact angle of 110° on ITO, evidenced the hydrophobic nature of synthesized C-dots. Fabrication of BHJ solar cells (in direct configuration) using PFO-DBT as donor and C-dots as acceptor, along with optimization gives significant solar cell J-V characteristics. The power conversion efficiency of nearly 3% with noticeable VOC of 0.85 V has been obtained. Replacement of fullerene with more economic C-dots lead to improvement in cost to performance ratio of polymer solar cells. Additionally, the stability measurement exhibits that the highly stable C-dots maintain high VOC in the device for quite longer duration.



Dr. Rajni is thankful to Council of Scientific and Industrial Research (CSIR) for providing Senior Research Fellowship to carry out the research work for completion of her doctorate under Academy of Scientific Innovation and Research (AcSIR). Also, authors acknowledge the Nano Research Facility (NRF) at IIT Delhi for HRTEM characterization.


  1. 1.
    C.W. Tang, Two-layer organic photovoltaic cell. Appl. Phys. Lett. 48, 183–185 (1986)ADSCrossRefGoogle Scholar
  2. 2.
    X.Y. Xu, Electrophoretic analysis and purification of fluorescent single-walled carbon nanotube fragments. J. Am. Chem. Soc. 126, 12736–12737 (2004)CrossRefGoogle Scholar
  3. 3.
    H. Liu, T. Ye, C. Mao, Fluorescent carbon nanoparticles derived from candle soot. Angew. Chem. Int. Ed. 46, 6473–6475 (2007)CrossRefGoogle Scholar
  4. 4.
    S. Chandra, P. Patra, S. Mitra, A. Goswami, Luminescent S-doped carbon dots: an emergent architecture for multimodal applications. J. Mater. Chem. B 1, 2375–2382 (2013)CrossRefGoogle Scholar
  5. 5.
    P. Mirtchev, E.J. Henderson, N. Soheilnia, C.M. Yip, G.A. Ozin, Solution phase synthesis of carbon quantum dots as sensitizers for nanocrystalline TiO2 solar cells. J. Mater. Chem. B 22, 1265–1269 (2012)CrossRefGoogle Scholar
  6. 6.
    X. Yan, X. Cui, B. Li, L.S. Li, Solution-processable graphene quantum dots as light absorbers for photovoltaics. Nano Lett. 10, 1869–1873 (2010)ADSCrossRefGoogle Scholar
  7. 7.
    H.B. Zhang, Z.H. Zhou, X. Dong, T. Chen, Raman spectra of MWCNTs and MWCNT-based H2 adsorbing system. Carbon 40, 2429–2436 (2002)CrossRefGoogle Scholar
  8. 8.
    D. Pan, J. Zhang, Z. Li, C. Wu, X. Yan, M. Wu, Observation of pH-, Solvent-, Spin-, and excitation-dependent blue photoluminescence from carbon nanoparticles. Chem. Commun. 46, 3681–3683 (2010)CrossRefGoogle Scholar
  9. 9.
    Z.H. Kang, E.B. Wang, L. Gao, S.Y. Lian, M. Jiang, C.W. Hu, L. Xu, One-step water-assisted synthesis of high-quality carbon nanotubes directly from graphite. J. Am. Chem. Soc. 125, 13652–13653 (2003)CrossRefGoogle Scholar
  10. 10.
    S. Mitra, S. Chandra, T. Kundu, R. Banerjee, P. Pramanik, A. Goswami, Rapid microwave synthesis of fluorescent hydrophobic carbon dots. RSC Adv. 2, 12129–12131 (2012)CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Rajni Sharma
    • 1
    Email author
  • Firoz Alam
    • 2
  • Ashok K. Sharma
    • 3
  • V. Dutta
    • 2
  • S. K. Dhawan
    • 1
  1. 1.CSIR-National Physical LaboratoryNew DelhiIndia
  2. 2.Centre for Energy StudiesIndian Institute of Technology DelhiNew DelhiIndia
  3. 3.National Centre for Photovoltaic Research and Education, IIT-BombayMumbaiIndia

Personalised recommendations