This page is updated and maintained by CHELLAPPAN Vijila.
Dr. CHELLAPPAN Vijila
Dr. CHELLAPPAN Vijila
Capability Group / Department:
Analysis & Characterisation
3 Research Link Singapore 117602
Advanced Energy Materials and Devices
Transient electrical and optical characterisation techniques
Charge transport and recombination studies using Time of Flight (TOF) Photoconductivity, Photoinduced Charge Extraction by Linearly Increasing Voltage (PhotoCELIV) technique and Dark Injection space charge limited current (DI-SCLC) techniques.
Excited state photophysics using transient absorption and photoluminescence spectroscopy
Deep Level Transient Spectroscopy (DLTS)
• Optoelectronic materials and devices
o Charge transport and recombination studies
o Metal-Organic Interfaces
o Device Physics
o Excited State Photophysics
• Transient optoelectrical spectroscopy
Apr 2012 - To- Date
Scientist III, IMRE, Singapore
Apr 2011 - Mar 2012
Scientist II (RSE-III), IMRE, Singapore
Apr 2009 - Mar 2011
Senior Research Engineer (RSE-III), IMRE, Singapore
Jan 2007 - Mar 2009
Senior Research Engineer (RSE-II), IMRE, Singapore
Jan 2003 - Dec 2006
Research Associate, IMRE, Singapore
Sep 2001 -Dec 2002
Post Doctoral Research Fellow, Abo Akademy University, Turku, Finland
Ph.D (Laser Technology), Anna University, Tamil Nadu, India, 2001
M.Sc (Physics), Presidency College, (University of Madras), Tamil Nadu, India, 1995
B.Sc (Physics), Women's Christian College, Nagercoil (M.S University), Tamil Nadu, India, 1993
Honours and Awards
Marquis Who's Who in Science and Engineering
Outstanding Contribution Partner Award from National Junior College, Singapore
Outstanding Contribution Partner Award from National Junior College, Singapore
Other Professional Appointments / Membership
Member, American Chemical Society
1. Bronson Philippa, Chellappan Vijila, Ronald D. White, Prashant Sonar, Paul L. Burn, Paul Meredith, Almantas Pivrikas, ‘Time-independent charge carrier mobility in a model polymer:fullerene organic solar cell’, Organic Electronics 16, 205(2015).
2. Hemlata Patil, Wang Xi Zu, Akhil Gupta, Vijila Chellappan, Ante Bilic, Prashant Sonar, Anushri Rananaware, Sidhanath V. Bhosalee and Sheshanath V. Bhosale, ‘A non-fullerene electron acceptor based on fluorene and diketopyrrolopyrrole building blocks for solution-processable organic solar cells with an impressive open-circuit voltage’, Phys.Chem.Chem.Phys., 16, 23837(2014).
3. Tan Mein Jin, Kajen Rasanayagam Sivasayan, Zhang Zhongxing, Chellappan Vijila, Chen Wei ‘Understanding Carrier Lifetime in Inverted Polymer Solar Cells with a Thick Electron Selective Layer’ ECS Solid State Letters, 3 (11) Q82-Q84 (2014).
4. Saeid Masudy-Panah, Goutam Kumar Dalapati, Tan Hui Ru, Chellappan Vijila, Dennis Tan Cheng Cheh, Chi Dongzhi, K. Radhakrishnan, Avishek Kumar, Elumalai Naveen Kumar, ‘p-CuO/n-Si heterojunction solar cells with high open circuit voltage and and photocurrent through the control of phase transformation and interfacial engineering’ Prog. Photovolt: Res. Appl. DOI: 10.1002/pip.2483 (2014).
5. Tan Mein Jin, LI Jun, Chellappan Vijila, Wang Rui, Zhong Shu, Seah Kang Yee, Chen Zhikuan, Chen Wei, ‘ZnO:polymer composite material to eliminate kink in J-V curves of inverted polymer solar cells’, ECS:Solid State Letters,3, 3, Q9-Q12 (2014).
6. Hiroyuki Matsuzaki, Sergey Gorelik, Jonathan Hobley, Gomathy Sandhya Subramanian, Chellapan Vijila, Evan Laurence Williams, Prashant Sonar, Akihiro Furube, Ryuzi Katoh, Samarendra Pratap Singh, Excited-state dynamics in diketopyrollopyrrole based copolymer for organic photovoltaics investigated by transient optical spectroscopy, Japanese Journal of Applied Physics, 53, 01AB11 (2014).
7. Chellappan Vijila, Samarendra P. Singh, Evan Williams, Prashant Sonar, Almantas Pivrikas, Bronson Philippa, Ronald White, Elumalai Naveen Kumar, S. Gomathy Sandhya, Sergey Gorelik, Jonathan Hobley, Akihiro Furube, Hiroyuki Matsuzaki, and Ryuzi Katoh, ‘Relation between charge carrier mobility and lifetime in organic photovoltaics’ Journal of Applied Physics, 114, 184503 (2013)
8. Naveen Kumar Elumalai, Tan Mein Jin, Vijila Chellappan, Rajan Jose, Suresh Kumar Palaniswamy, Sundaramurthy Jayaraman, Hemant Kumar Raut, Seeram Ramakrishna, ‘Electrospun ZnO Nanowire Plantations in the Electron Transport Layer for High-Efficiency Inverted Organic Solar Cells’, ACS Appl. Mater. Interfaces, 5, 9396 (2013).
9. Naveen Kumar Elumalai, Chellappan Vijila, Rajan Jose, Kam Zhi Ming, Amitaksha Saha and Seeram Ramakrishna, ‘Simultaneous improvements in power conversion efficiency and operational stability of polymer solar cells by interfacial engineering’ Phys.Chem. Chem. Phys., 15, 19057 (2013).
10. Mein Jin Tan, Shu Zhong, Rui Wang, Zhongxing Zhang, Vijila Chellappan, Wei Chen, ‘Biopolymer as an electron selective layer for inverted polymer solar cells’, Applied Physics Letters, 106,063303-4(2013).
11. Evan L Williams, Sergey Gorelik, InYee Phang, Michel Bosman, Chellappan Vijila, Gomathy Sandhya Subramanian, Prashant Sonar, Jonathan Hobley, Samarendra P Singh, Hiroyuki Matsuzaki, Akihiro Furube, Ryuzi Katoh, ‘Nanoscale phase domain structure and associated device performance of organic solar cells based on a diketopyrrolopyrrole polymer, RSC Adv.,3 (43), 20113-20124(2013).
12. Naveen Kumar Elumalai, Amitaksha Saha, Vijila Chellappan, Jose Rajan, Jie Zhang, Seeram Ramakrishna, ‘Enhancing the stability of polymer solar cells by improving the conductivity of the nanostructured MoO3 hole-transport layer’, Phys. Chem. Chem. Phys.,15, 6831(2013).
13. R. S. Kajen, N. Chandrasekhar, K. L. Pey, C. Vijila, M. Jaiswal, S. Saravanan, Andrew M. H. Ng, C. P. Wong, and K. P. Loh, ‘Charge transport in lightly reduced graphene oxide: A transport energy perspective’ Journal of Applied Physics 113, 063710 (2013).
14. R. S. Kajen, N. Chandrasekhar, K. L. Pey, C. Vijila, M. Jaiswal, S. Saravanan, Andrew M. H. Ng, C. P. Wong, and K. P. Loh, ‘Trap Levels in Graphene Oxide: A Thermally Stimulated Current Study’, ECS Solid State Letters, 2 (2) M17-M19 (2013).
15. P. S. Archana, E. Naveen Kumar, C. Vijila, S. Ramakrishna, M. M. Yusoff and R. Jose, ‘Random nanowires of nickel doped TiO2 with highsurface area and electron mobility for high efficiency dye-sensitized solar cells’ Dalton Transactions,42, 1024(2013).
16. E. Naveen Kumar Elumalai, R Jose, P. S. Archana, Vijila C, and Seeram Ramakrishna,‘Charge Transport through Electrospun SnO2 Nanoflowers and Nanofibers: Role of Surface Trap Density on Electron Transport Dynamics’ J. Phys. Chem. C, 116, 22112 (2012)
17. E. Naveen Kumar, L Man Yin, Vijila C, Zhang Jie, Z. Peining, and S. Ramakrishna, ‘Effect of C60 as an electron buffer layer in polythiophene-methanofullerene based bulk heterojunction solar cells’, Phys. Status Solidi A 209, 8, 1592 (2012).
18. R.S. Kajen, N. Chandrasekhar, Ming Hua Ng, Seok Hong Goh, Kin Leong Pey and C.Vijila, ‘Ballistic Electron Emission Microscopy Study of Charge Transport Across an Au/Graphene-Oxide/Modified-Si Stack’, ECS Solid State Lett.1, 2, M13-15 (2012).
19. R. S. Kajen, N. Chandrasekhar, K. L. Pey and C.Vijila, ‘Trap Energy Levels in Graphene Oxide Determined by Ballistic Electron Emission Spectroscopy’ ECS Solid State Lett.1, 5, M27-M28 (2012).
20. Zhen Fang, C.Vijila, Richard D.Webster, Lin Ke, Tianfu Zhang,Bin Liu and Yee-Hing Lai, ‘Bridged-triarylamine starburstoligomers as hole transporting materials for electroluminescentdevices’ J.Mater.Chem., 22, 15397(2012).
21. E. Naveen Kumar, R. Jose, P. S. Archana, C. Vijila, M. M. Yusoff and S. Ramakrishna, ‘High performance dye-sensitized solar cells with record open circuit voltage using tin oxide nanoflowers developed by electrospinning’ Energy &Environmental Science, 5, 5401 (2012).
22. Mein Jin Tan, Wei Peng Goh, Jun Li, Gaurav Pundir, C. Vijila and Zhikuan Chen, Charge mobility and recombination in a new hole transporting polymer and its photovoltaic blend, ACS:Applied Materials and Interfaces, 2, 1414-1420 (2010).
23. P. S. Archana, R. Jose, T. Mein Jin, C. Vijila, S. Ramakrishna, ‘Structural and Electrical Properties of Nb-doped Anatase TiO2 Nanowires by Electrospinning’ Journal of American Ceramic society, 93 (12), 4096 – 4102 (2010).
24. L. Ke, S.B Dolmanan, C. Vijila, S.J.Chua, Y.H. Han, and T. Mei, ‘Investigation of the device degradation mechanism in pentacene-based thin film transistors using low frequency noise spectroscopy, IEEE Transactions on Electron Devices, 57,385 (2010).
25. Ging-Meng Ng, Wei-Peng Goh, C. Vijila, Hoi Lam Tam, Furong Zhu ‘Improved cathode for semitransparent organic solar cells’ IEEE-Advances in Optoelectronics and Micro/Nano-Optics (AOM), DOI:10.1109/AOM.2010.5713600 (2010).
26. Vijila C, Ging Meng Ng, Mein Jin Tan, Wei-Peng Goh, and Furong Zhu, ‘Imbalanced charge mobility in oxygen treated polythiophene/fullerene based bulk heterojunction solar cells’ Applied Physics Letters, 95, 263305(2009)
27. P. S. Archana, R. Jose, C. Vijila, and S. Ramakrishna, ‘Improved Electron Diffusion Coefficient in Electrospun TiO2 Nanowires’ J. Phys. Chem. C, 113, 21538 (2009).
28. Manoj Parameswaran a, Ganapathy Balaji a, Sajini Vadukumpully a, Suresh Valiyaveetil, Tan Mein Jin, C.Vijila, Zhu Furong, ‘Charge transport studies in fluorene–Dithieno[3,2-b:2,3-d] pyrrole-oligomer using time-of-flight photoconductivity method’, Organic Electronics 10, 1534 (2009).
29. G. M. Ng, C. Vijila, W. P. Goh, F. R. Zhu, ‘Translucent Polymer Solar Cells’, ECS Trans. 18, 869 (2009).
30. Weihua Tang, Vijila C, Minghui Liu, Zhi-Kuan Chen, and Lin Ke, ‘Hole Transport in Poly[2,7-(9,9-dihexylfluorene)- alt-bithiophene] and High-Efficiency Polymer Solar Cells from Its Blends with PCBM’, ACS: Applied Materials and Interfaces, 1, 1467 (2009).
31. Ke Lin, Surani Bin Dolmanan, Lu Shen, C. Vijila, Soo Jin Chua, Rui-Qi Png, Perq-Jon Chia, Lay-Lay Chua, and Peter K.-H. Ho ‘Low frequency noise analysis on organic thin film transistors’, Journal of Applied Physics, 104, 124502 (2008).
32. C.Vijila, Markus Westerling, Harri Aarnio, Ronald Österbacka, Huang Chun, Chen Zhikuan, Zhang Xinhai, Zhu Furong and Chua Soo Jin, ‘Nature and dynamics of photoexcited states in an electroluminescent poly (phenylene vinylene -co- fluorenylene vinylene) based π-conjugated polymer’, Journal of Photochemistry and photobiology; A: Chemistry, 199, 358 (2008).
33. C.Vijila, Ng Ging Meng , Chen Zhi Kuan, Zhu Furong and Chua Soo Jin, ‘Charge transport studies in electroluminescent biphenylyl substituted PPV derivatives using time-of-flight photoconductivity method, Journal of Polymer Science: Part B: Polymer Physics, 46, 1159 (2008).
34. Ke L, Bin Dolmanan S, Shen L, Vijila C, Chua SJ, Png RQ, Rui-Qi, Chia PJ, Chua LL, Ho PKH, ‘Impact of self-assembled monolayer on low frequency noise of organic thin film transistors', Applied Physics Letter, 93, 153507 (2008).
35. Lin Ke, Vijila Chellappan, Bin Liu, Zhen Xian Soh, Rina Hui Ting Soh and Soo Jin Chua, ‘Electrical and optical properties of an alcohol soluble aminoalkyl-substituted cationic conjugated polymer’ Jl. of Materials Science, 43, 2818 (2008).
36. L. Ke, R.S. Kumar, C. Vijila, S.J. Chua and X.W. Sun, ‘Correlation of Current Noise behaviour and dark spot formation in organic light emitting diodes’, IEEE-Electron Device Letters, 29, 67 (2008) .
37. C. Vijila, Almantas Pivrikas, Huang Chun, Chen Zhikuan, Ronald Österbacka and Chua Soo Jin, ‘A study of charge transport in a novel electroluminescent poly (phenylene vinylene -co- fluorenylene vinylene) based -conjugated polymer’ Organic Electronics 8, 8 (2007).
38. LinKe, Ronald Cai Cheng Han, C.Vijila and Soo Jin Chua, ‘Transport Study of a novel polyfluorene/poly-phenylenevinylene) copolymer by various mobility models’, Jl. of Materials Science, 42, 9176 (2007).
39. Renu Ravindranath, C.Vijila, Parayil Kumaran Ajikumar, Fathima Shahitha Jahir Hussain, Hezhou Wang, Chua Jin Soo, Wolfgang Knoll, Suresh Valiyaveettil, ‘Photophysical properties and film morphology of a new class of poly(p-phenylenes) bearing amphiphilic side chains’ J. Phys. Chem. B, 110, 25958 (2006).
40. Lin Ke, Soo Jin Chua, Ronald Cai, Cheng Han, Lin Ting Ting and C. Vijila, ‘Brownian motion field dependent mobility theory of hopping transport process’, Journal of Applied Physics, 99, 1 (2006).
41. D.Mangaiyarkarasi, M.B.H.Breese, O.Y. Sheng and C.Vijila, ‘Controlled blue-shift of the resonant wavelength in porous silicon microcavities using ion irradiation’, Applied Physics Letter 89, 021910 (2006).
42. Chun Huang, Chang-Gua Zhen, Siew Ping Su, C. Vijila, Bavani Balakrisnan, Mark Dai Joong Auch, Kian Ping Loh, Zhi-Kuan Chen, ‘Highly efficient electroluminescent biphenylyl-substituted poly(p-phenylenevinylene)s through fine tuning the polymer structure' Polymer 47, 1820 (2006).
43. C. Vijila, Bavani Balakrisnan, Chun Huang , Zhi-Kuan Chen, Chang-Gua Zhen, Mark Dai Joong Auch, Soo Jin Chua, ‘A study of charge mobility characteristics in a series of biphenylyl substituted PPV derivatives’, Chemical Physics Letters, 414, 393 (2005).
44. M. Westerling, C. Vijila, R. Osterbacka and H. Stubb, ‘Dispersive and nondispersive recombination of photoexcitations in disordered organic solids, Physical Review B69, 245201 (2004).
45. M.Westerling, C.Vijila, R. Österbacka, H. Stubb, ‘Optical studies of excited-state relaxation in poly(9,9-dihexylfluorene-co-benzothiadiazole)’, Physical Review B67, 195201, (2003).
46. M. Westerling, C. Vijila, R. Österbacka, H. Stubb, ‘Bimolecular recombination in regiorandam poly(3-hexylthiophene)’, Chemical Physics, 286, 315 (2003).
47. C. Vijila and A. Ramalingam, “Photo physical characteristics of Coumarin 485 dye doped poly (methyl methacrylate) modified with various additives”, Journal of Materials Chemistry, 11, 749 (2001).
48. C Vijila, A. Ramalaingam, P.K. Palanisamy and V.Masilamani, “Role of dipole moment of solvents in formation and stabilization of the TICT states in coumarin 445 under nitrogen laser excitation”, Spectrochimica Acta A: Molecular spectroscopy, 57(3), 493 (2001).
49. C. Vijila, A. Ramalingam, V.S. Gowri and K.Sivakumar, ‘Effect of solvent on the photophysical properties of substituted imidazonaphthyridine derivative’, Spectrochimica Acta A: Molecular spectroscopy, 56(5), 983 (2000).
50. Ramalingam and C. Vijila, ‘A study of spectral and gain characteristics of substituted amino coumarin under nitrogen laser excitation, Journal of Molecular Liquids, 81, 237 (1999).