Arun Chattopadhyay
  • 1996 – Present   Faculty Member           IIT Guwahati
  • 1992-1995         Post Doctoral Fellow   Stanford University   with Steve Boxer
  • 1988-1992         Ph.D.                           Columbia University with Rich Bersohn
  • 1986 – 1988       M. Sc.                         IIT Kanpur  
  • 1983 – 1986       B.Sc.                           Presidency College, Calcutta

 

Others

  • 1991                  Research                      Brookhaven National Laboratory
  • 1987                  Research                      TIFR, Mumbai

 

Awards and Distinctions.

Pegram Award                                                           Columbia University      1992

J. M. Miller Teaching Assistant Award                        Columbia University      1989

R. B. Ghosh Travel Award                                         Calcutta University        1988

Best Undergraduate Student in Chemistry Award        IIT Kanpur                   1988

Student Benefit Fund Award                           IIT Kanpur                   1987-88

Student Merit Award                                      IIT Kanpur                   1987

National Scholarship                                                   Govt. of India               1981-88

Research Interest.

We are interested in the broad areas of Nano Science & Technology and Micro & Nano Fluidics.  The work may involve synthesizing application oriented smart materials with nanometer dimensions.  It could just as well be finding a new method of single or multiple color nanolithography.  Designing micro and nanofluidic devices for scientific and industrial application is also an aim of our research.  In addition, we are interested in working out the basic principles that would lead to the application in the above fields.  Furthermore, we are interested in understanding surface and interfacial phenomena that would lead to potential applications in modern technology.  We are committed to devote a little bit of time designing newer experiments for the modern undergraduate laboratory.

Research Activity

At IIT-Guwahati, we have currently been working on nanoscience and technology.  We have for the first time introduced the concept of color nanolithography.  This has been achieved in the form of generation of color patterns with submicron scale dimension on two - dimensional surfaces of glass and plastic substrates.  Soft lithography based approach has been applied using commercially available compact discs (CDs) as the mold.  The submicron dimension parallel lines of the mold have been transferred to the colored macroscopic lines drawn using permanent marker pens on glass and plastic surfaces.  In addition, arrays of ink dots have been created using the same mold.  The idea is to store information in “true” color so that the retrieval time is faster and efficient.

 


Figure 1.  Our method of color nanolithography.  See Nano Letters 2001 1(8), 409 for further details.

 

 


We have also developed a method of generating polymer - nanoparticle composite using H2O2 as the reducing agent (HAuCl4 to Aun) as well as oxidizing agent (polymerization of aniline).  We have found that the electrical conductivity of the polymer increases hundred fold by incorporating a small amount of Au nanoparticles.  Earlier polymer – nanoparticle composites were made by mixing polymer and nanoparticles prepared separately.  In our method, the composite was synthesized in the same aqueous solution using a mixture of HAuCl4, H2O2 and aniline.  This method has the advantage over other methods as the composite is made first by synthesizing the nanoparticles followed by polymerization over it.  In the other methods, the question of inhomogeneous mixing might pose a serious problem in the generation of favorable materials.

 

            We have also introduced a method of photolithography in thin polymer films at the air-water interface.  In this method, we have taken advantage of simultaneous chemical reaction catalyzed polymerization and photochemical polymerization of the film grown on the interface.  An optical transparency gradient was generated in the film that appeared in the form of writing on the films.


 



           

 


Figure 2. A new simultaneous chemical and photochemical reaction based method of lithography.  Here the letters “ I I T ” are imprinted on polyaniline films.  If you want to know more about this then see J. Phys. Chem. B. 2002, 106, 4343.

 

We have also been working on the application of UV-visible and FTIR spectroscopy towards understanding the drainage behavior of single soap bubbles.  We have observed Marangoni effect driven controlled fluid movements up along the films of a soap bubble.

 


 


Figure 3.  Time-dependent UV-visible absorption spectra of a dye representing controlled fluid flow (slow a and fast b) up along a soap bubble.  See J. Phys. Chem. B. 2001, 105, 12503 for more on this.

 

 

 

 

 

 

 

 

Publications

 

1.      Synthesis of Au nanoparticle - conductive polyaniline composite using H2O2 as oxidising as well as reducing agent

Tridib Kumar Sarma, Devasish Chowdhury, Anumita Paul and Arun Chattopadhyay, Chem. Commun, 2002, 10, 1048.

 

2.      Lithography by Simultaneous Chemical and Photo-chemical Polymerization of

Aniline at the Air-Water Interface

Devasish Chowdhury, Anumita Paul and Arun Chattopadhyay, J. Phys. Chem. B. 2002, 106, 4343.

 

3.      Visible Spectroscopic Observation of Controlled Fluid Flow up Along a Soap Bubble Film from a Pool of Solution

Tridib Kumar Sarma and Arun Chattopadhyay J. Phys. Chem. B. 2001, 105, 12503.

 

4.      Simultaneous Measurement of Flowing Fluid Layer and Film Thickness of a Soap Bubble Using UV-Visible Spectrophotometer.

Tridib Kumar Sarma and Arun Chattopadhyay, Langmuir, 2001, 17(21), 6399.

 

5.      Patterning Design in Color at the Submicron Scale

Devasish Chowdhury, Anumita Paul, and Arun Chattopadhyay Nano Letters 2001 1(8), 409.

 

List of publications

 

Conference

 

Invited talk

 

1.      Fourth National Symposium in Chemistry organized by Chemical Research Society of India, National Chemical Laboratory, Pune, 2002.

2.      Symposium on Recent Trends in Photochemical Sciences, Regional Research Laboratory, Trivandrum, 2001.

3.      First National Symposium in Chemistry organized by Chemical Research Society of India, Indian Institute of Science, Bangalore, 1999.

4.      Symposium on Recent Trends in Photochemical Sciences, Regional Research Laboratory, Trivandrum, 1998.

5.      National Symposium on Radiation and Photochemistry, Andhra University, Vishakapattnam, 1997.

 

Oral Presentation

 

1.         73 rd Americal Chemical Society  Colloid and Surface Science Symposium, MIT, Cambridge, Massachusetts 1999.

 

Poster Presentation

 

1.         Fourth National Symposium in Chemistry organized by Chemical Research Society of India, National Chemical Laboratory, Pune, 2002 (with Devasish Chowdhury and Anumita Paul).

2.         Second National Symposium in Chemistry, Indian Institute of Chemical Technology, Hyderabad, 2000 (with Tridib Kumar Sarma).

Sponsored Projects

1.         Unsupported Membranes: A Simple Approach       Council of Scientific and Industrial Research, New Delhi, India.

2.         Nanolithography in Color and Design of Microfluidic Devices      Department of Science and Technology, New Delhi, India

            (Under Nanomaterials Science & Technology Initiative)

Students

Ph. D.

1.                  Ms. Gitanjali Majumdar 2002 (gitanjali@iitg.ernet.in)

2.                  Mr. S. Manikandan (Deceased) 2001

3.                  Mr. Tridib Kumar Sarma 1999 (tridib@iitg.ernet.in)

M. Sc.

1.                  Ms. Pompi Hazarika 2002 (pompi_iitg@yahoo.com)

Summer Project

1.                  Mr. Suryya Protim Sarkar (REC Tiruchirappalli) – 2002 (CL10038@rect.ernet.in)

2.                  Mr. Dipankar Kalita (REC Tiruchirappalli)- 2002 (CL10012@rect.ernet.in) 

3.                  Mr. Diganta Barkakaty (Assam Engineering College) 2002

4.                  Mr. Mriganka Chakraborty (REC Tiruchirappalli) – 2001 (CL19919@rect.ernet.in)

 

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