Thalappil Pradeep

Thalappil Pradeep

Professor T. Pradeep in his laboratory 2008
Nationality Indian
Fields Molecular materials and surfaces
Institutions Indian Institute of Technology Madras
Alma mater Indian Institute of Science, Bangalore

Thalappil Pradeep is a professor in the Department of Chemistry[1] at the Indian Institute of Technology Madras.[2]

Education

Pradeep[3] earned a PhD degree in chemical physics working with Professors C. N. R. Rao[4] and M. S. Hegde at the Indian Institute of Science, Bangalore.[5] Subsequently, he spent about two years as a post-doctoral fellow at the University of California, Berkeley[6] and Purdue University, Indiana.[7] Since then, he has been working in the Indian Institute of Technology Madras,[2] where he is a full professor. He also held visiting positions at Purdue University,[8] Leiden University, in the Netherlands,[9] EPFL, Switzerland,[10] the Institute of Chemistry, Taiwan,[11] Pohang University of Science and Technology, South Korea[12] and the University of Hyogo, Japan.[13]

Research

Pradeep's work is in the area of molecular materials and surfaces. In his formative years, he measured the very first vibrationally resolved photoelectron spectrum of Ar2[14] and discovered a novel transition metal ion, NiH2+.[15] Currently most of his work is on nanoparticles and ice surfaces. His group studied the dynamics of monolayers in monolayer protected nanoparticles and has shown that monolayers are rotationally frozen on nanoparticle surfaces and do not exist in a 'rotator phase', as believed earlier.[16] His group found a 'transverse electrokinetic effect', in which a potential is generated on nanoparticle assemblies anchored on surfaces, when a liquid flows over them.[17] He showed that the equilibrium constant of the prototypical proton transfer reaction, NH3 + HCl → NH4Cl, is orders of magnitude lower on ice.[18] More recently he found that diffusion of chemically similar molecules through ultra thin ice films exhibits several surprise effects.[19] A new structural transition on the top-most layers of ice surfaces has been discovered at low temperatures.[20]

Results

Pradeep discovered that in the presence of metal nanoparticles, single walled carbon nanotube (SWNT) bundles emit light in the visible region of the electromagnetic spectrum, irrespective of whether it is metallic or semiconducting.[21] This is primarily attributed to the increase in the number of defects introduced by nanoparticle binding, which leads to the complete loss of metallicity of the tubes. While the visible light fluorescence has shown large potential in sensing, many novel applications are likely to be discovered through the loss of metallic nature of SWNTs.

His recent research is mostly concerned with anisotropic nanostructures[22][23] and luminescent noble metal clusters.[24][25][26] He found that noble metal nanoparticles can completely degrade halocarbons into amorphous carbon and metal halides.[27] There are many important aspects of this discovery: the complete degradation of halocarbons, and extension of the study to toxic pesticides (as many of them are halocarbons),[28] its eco-friendly nature (as the end-products are harmless), the efficient removal mechanism of pesticide residues in drinking water[29] and simple visual color based detection systems for pesticide detection.[30] Due to zero electricity usage, this technology is likely to be of use to rural populations affected by pesticide contamination. The technology has been commercialised and a nanoparticle-based water filter has been introduced in the market in partnership with Eureka Forbes Limited.[31] It is the very first nanoparticle based water filter.[32]

Pradeep discovered an unusual proton transfer phenomenon on ice surfaces, and showed that metastable species can be stabilised at ice surfaces. In a recent study he has shown that while the diffusion of CCl4 is blocked by a three to four monolayers of ice, hundreds of monolayers are needed to block the transport of CHCl3 and CH2Cl2.[19] The oscillation of vapour pressure of CO2 over melting ice is another discovery.[33] Several studies have confirmed that this is a general phenomenon concerning the dynamics of the gas phase above a condensed system during its phase transition. The bond-specific processes at the top layers of ice are studied using an in-house developed ultrahigh vacuum instrument working at 10−11. These studies are important for the understanding of chemical reactions involving ice particles in the atmosphere.

Views on nanotechnology

Pradeep has been advocating the use of noble metal based nanotechnology for purifying the environment.[34] As scientific understanding of the health effects of contaminants increases, it is likely that their allowed limits will be continuously revised. The contaminants levels are expected to reach molecular limits in the years to come. This implies that the technologies we use have to become molecule-specific and nanotechnology becomes the obvious choice.[35]

Books

Technology

Popular science

Kunjukanangalku Vasantham,[36] written in Malayalam, is about Nanoscience and Nanotechnology. The title may be translated as, "The Springtime of Small Particles". This book won the 2010 Kerala Sahitya Akademi Award for Knowledge Literature.[37][38]

References

  1. ↑ "Department of Chemistry". Chem.iitm.ac.in. Retrieved 18 October 2013.
  2. ↑ 2.0 2.1 "Indian Institute of Technology Madras". Iitm.ac.in. Retrieved 18 October 2013.
  3. ↑ "Profile of Professor T. Pradeep". Dstuns.iitm.ac.in. Retrieved 18 October 2013.
  4. ↑ "C. N. R. Rao". Jncasr.ac.in. 30 June 1934. Retrieved 18 October 2013.
  5. ↑ "Indian Institute of Science, Bangalore". Iisc.ernet.in. Retrieved 18 October 2013.
  6. ↑ "University of California, Berkeley". Berkeley.edu. Retrieved 18 October 2013.
  7. ↑ Purdue Marketing & Media, Purdue University. "Purdue University, Indiana". Purdue.edu. Retrieved 18 October 2013.
  8. ↑ Purdue Marketing & Media, Purdue University. "Purdue University, USA". Purdue.edu. Retrieved 18 October 2013.
  9. ↑ "Leiden University, Netherlands". Leiden.edu. Retrieved 18 October 2013.
  10. ↑ "EPFL, Switzerland" (in French). Epfl.ch. 17 September 2013. Retrieved 18 October 2013.
  11. ↑ Institute of Chemistry, Taiwan
  12. ↑ "Pohang University of Science and Technology, South Korea". Postech.ac.kr. Retrieved 18 October 2013.
  13. ↑ "University of Hyogo, Japan". U-hyogo.ac.jp. Retrieved 18 October 2013.
  14. ↑ Photoelectron spectroscopy of rare-gas dimers revisited: vibrationally resolved photoelectron spectrum of argon dimer, T. Pradeep, B. Niu and D. A. Shirley, J. Chem. Phys., 98 (1993) 5269 doi:10.1063/1.464926
  15. ↑ Concentrated hydrogen rearrangement in C10H10Ni+. and the formation of NiH2+. , T. Pradeep, J. S. Patrick, B. Feng, T. Ast, S. A. Miller, and R. G. Cooks, J. Phys. Chem., 99 (1995) 2941 doi:10.1021/j100010a001
  16. ↑ Towards Understanding Structure and Phase Transitions of Self-Assembled Monolayers on Two- and Three- Dimensional Surfaces: An Overview of Current Efforts, N. Sandhyarani and T. Pradeep, Int. Rev. Phys. Chem., 22, Issue 2(2003) 221–262 doi:10.1080/0144235031000069705
  17. ↑ Flow induced transverse potential in nanoparticle assemblies, C. Subramaniam, T. Pradeep and J. Chakrabarti, Phys. Rev. Lett., 95 (2005) 164501(1–4) doi:10.1103/PhysRevLett.95.164501
  18. ↑ Reactive ion scattering from pure and mixed HCl, NH3 and D2O surfaces, Seong-Chan Park, Kye-Won Maeng, T. Pradeep and H. Kang, Nuclear Instruments and Methods, B 182 (2001) 193–199 doi:10.1016/S0168-583X(01)00675-9
  19. ↑ 19.0 19.1 Probing the difference in diffusivity of chloromethanes through water ice in the temperature range of 110–150 K, Jobin Cyriac and T. Pradeep, J. Phys. Chem. C., 111 (2007) 8557–8565 doi:10.1021/jp068435h
  20. ↑ Structural reorganization on amorphous ice films below 120 K revealed by near-thermal (~1 eV) argon ion scattering, Jobin Cyriac and T. Pradeep, J. Phys. Chem. C., 112 (2008) 5129–5135 doi:10.1021/jp108283z
  21. ↑ Subramaniam, C.; Sreeprasad, T.; Pradeep, T.; Pavan Kumar, G.; Narayana, C.; Yajima, T.; Sugawara, Y.; Tanaka, H.; Ogawa, T.; Chakrabarti, J. (2007). "Visible Fluorescence Induced by the Metal Semiconductor Transition in Composites of Carbon Nanotubes with Noble Metal Nanoparticles". Physical Review Letters 99 (16). doi:10.1103/PhysRevLett.99.167404.
  22. ↑ Anisotropic nanomaterials: Structure, growth, assembly, and functions, P. R. Sajanlal, T. S. Sreeprasad, A. K. Samal and T. Pradeep, Nano Reviews, 2 (2011) 5883 doi:10.3402/nano.v2i0.5883
  23. ↑ Properties and Applications of Colloidal Nonspherical Noble Metal Nanoparticles, Tapan K. Sau, Andrey L. Rogach, Frank Jackel, Thomas A. Klar and Jochen Feldmann, Advanced Materials 22 (2010) 1805–1825 doi:10.1002/adma.200902557
  24. ↑ Quantum Clusters of Gold Exhibiting FRET, M. A. Habeeb Muhammed, Ajay Kumar Shaw, Samir Kumar Pal and T. Pradeep, J. Phys. Chem. C., 112 (2008) 14324-14330 doi:10.1021/jp804597r
  25. ↑ Luminescent quantum clusters of gold in bulk by BSA-induced core etching of nanoparticles: Metal ion sensing, metal enhanced luminescence and biolabeling, Madathumpady Abubaker Habeeb Muhammed, Pramod Kumar Verma, Samir Kumar Pal, Archana Retnakumari, Manzoor Koyakutty, shantikumar Nair, and T. Pradeep, Chem. Eur. J., 16 (2010) 9925-10259 doi:10.1002/chem.201000841
  26. ↑ Ag9 quantum cluster through a solid state route, Thumu Udaya B. Rao, Boodeppa Nataraju and T. Pradeep, J. Am. Chem. Soc., 132 (2010) 16304 – 16307 doi:10.1021/ja105495n
  27. ↑ "Halocarbon mineralization and catalytic destruction by metal nanoparticles, A. Sreekumaran Nair and T. Pradeep, Current Science., 84 (2003) 1560–1564" (PDF). Retrieved 18 October 2013.
  28. ↑ Detection and extraction of endosulfan by metal nanoparticles, A. Sreekumaran Nair, Renjis T. Tom, and T. Pradeep, J. Environ. Monitoring., 5 (2003) 363–365 doi:10.1039/B300107E
  29. ↑ Extraction of chlorpyrifos and malatheon from water by metal nanoparticles, A. Sreekumaran Nair and T. Pradeep, J. Nanoscience and Nanotechnology, 7 (2007) 1–7 doi:10.1166/jnn.2007.733
  30. ↑ Enhanced visual detection of pesticides using gold nanoparticles, K. P. Lisha, Anshup and T. Pradeep, J. Envi. Sci. Health B, Pesticides, Food Contaminants and Agricultural Wastes, 44 (2009) 697–705 doi:10.1080/03601230903163814
  31. ↑ "Aquaguard Total Gold Nova – World's first nanotechnology based filter". Eurekaforbes.com. Retrieved 18 October 2013.
  32. ↑ "Pesticide filter debuts in India, Killugudi Jayaraman, Chemistry World, April 20, 2007". Rsc.org. 20 April 2007. Retrieved 18 October 2013.
  33. ↑ Concentration of CO2 over melting ice oscillates, S. Usharani, J. Srividhya, M. S. Gopinathan and T. Pradeep, Phys. Rev. Lett., 93 (2004) 048304-4 doi:10.1103/PhysRevLett.93.048304
  34. ↑ Noble metal nanoparticles for water purification: A critical review, T. Pradeep and Anshup, Invited critical review, Thin Solid Films, 517 (2009) 6441–6478 doi:10.1016/j.tsf.2009.03.195
  35. ↑ "Pradeep on the need for nanotechnology for drinking water purification – CII Journal". Tech2transfer.com. Retrieved 18 October 2013.
  36. ↑ "Kunjukanangalku Vasantham" D. C. Books, Kottayam, 2007
  37. ↑ "Kerala Sahitya Akademi Award for Knowledge Literature, 2010" (PDF). Retrieved 18 October 2013.
  38. ↑ "Books authored by Professor T. Pradeep". Dstuns.iitm.ac.in. Retrieved 18 October 2013.

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