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The research paper of Deep Jariwala (final year student in dept. of Metallurgical Engineering) was published in the premier materials science journal, Nature Materials. It has received a lot of media attention the world over. The relevant web links of the news articles are pasted below.
The research was headed by Prof. P. M. Ajayan (Metallurgy 1985), Deep Jariwala and Dr. Anchal Srivastava (Science faculty, Dept. of Physics, BHU), who are co-authors in the work. The paper published was titled as “Atomic layers of hybridized boron nitride and graphene domains”.
Deep Jariwala is also a recipient of 2010 Student Achievement Award (given out on IT-Day on March 19, 2010) by IT-BHU Global Alumni Association.
 Deep Jariwala |  Prof. P M. Ajayan |  Dr. Anchal Srivastava |
Deep Jariwala
Senior undergraduate student,
Dept. of Metallurgical Engineering,
IT-BHU, Varanasi.
Email: deep29jariwala@gmail.com
Home Page: http://sites.google.com/site/deepjariwalasite/
Prof. P. M. Ajayan
Benjamin M. and Mary Greenwood Anderson Professor of Engineering
Department of Mechanical Engineering & Materials Science, Rice University,
Houston, Texas, USA.
(Metallurgy 1985 alumnus from IT-BHU)
Email: ajayan@rice.edu
Home Page: http://www.owlnet.rice.edu/~rv4/Ajayan/
Dr. Anchal Srivastava
Lecturer,
Department of Physics
Banaras Hindu University, Varanasi.
Email: anchalbhu@gmail.com
Home page:
http://www.bhu.ac.in/science/faculty/Department_of_Physics_Dr_A_Srivastava.htm
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Chronicle interviews Deep Jariwala about his recent research publication:
Q-1: Please describe your research project
Our project involved synthesis of a new two dimensional hybrid material by mixing graphene and hexagonal boron nitride (h-BN), two structurally similar materials but having remarkably opposite electronic properties. This new system allows us to synthesize 2 dimensional semiconducting materials with tunable electronic and optical properties which opens up new possibilities for making novel electronic and optical devices. This is very first time it has been demonstrated that graphene and h-BN can be combined into a single atomic layer hybrid. Moreover the remarkable new properties it shows are very exciting from a materials research perspective. This research promises to open up a whole new area in research of 2 dimensional semiconductors as well as graphene band gap engineering. This research is also promising from industrial application point of view. This is because we have managed to synthesize these films on large areas and the process can be easily scaled to synthesize them on 6-10 inch wafers.
Q-2: How the research was carried out?
The explosion in graphene research started after 2004 when graphene was first isolated on an insulating substrate. Right from the very beginning people realized its potential in replacing silicon and taking electronic gadgets to a whole new level. This is because graphene shows superior electronic properties than silicon in many respects and thus promises to make computers and electronics faster, smaller and flexible. However, nothing practical can be achieved on an industrial scale until large area synthesis of high quality graphene can be realized and a band gap is opened in its electronic structure. Thus our research was focused on band gap engineering in graphene by doping it with boron and nitrogen simultaneously.
However, on performing certain theoretical calculations it was realized that boron and nitrogen will segregate and form hexagonal boron nitride domains. The central idea was to mix graphene and hexagonal boron nitride which are structurally very similar materials. Although both these materials are structurally very similar, they are opposite in nature of their electronic properties i.e. while graphene is a semimetal, h-BN is a wide band gap insulator. We thought that by mixing both of them new hybrid electronic materials with tunable bandgap and electronic properties can be realized. We attempted to synthesize this hybrid material in a state of the art thermal CVD facility at Prof. Ajayan’s lab. A copper substrate was used for deposition of the films. Later these films were transferred onto other substrates and characterized by various techniques like XPS, AFM, Raman spectroscopy, TEM, EELS, SEM and UV-Visual spectrophotometery to confirm the predicted structure and properties. Then using conventional lithographic techniques micron size electronic devices were fabricated and tested.
Since it was a new material hypothesized as well as synthesized, the experimental observations and theoretical predictions had to be correlated. For theoretical modeling we sought help from a group based in University of Utah. Besides these there were Dr. Lijie and Dr. Li (post docs at Prof. Ajayan’s group) who are the lead authors. There were also people involved form AIST, Japan; National High Magnetic field laboratory, Florida, USA and Praire View A & M University, Texas, USA. This research was multidisciplinary in nature and involved inputs from people with varied backgrounds like materials science, physics, chemistry and electronics. The team work and co-ordination was very important for effective and timely realization of the goals. Moreover a sound understanding of the problem among all the members was essential in addition to knowing each others forte and weakness. In recent times most of the outstanding research works are multidisciplinary in nature and hence involve teamwork with members from a variety of disciplines.
Q-3: What advice will you give to students to work on a research paper?
Over the last decade or so there has been a tremendous rise in the number of scientific journals throughout the world. Therefore one has a lot of choices/options in publishing ones research work. However to publish in the most reputed journals the effort has to be extraordinary. I would advice students to do a lot of literature reading. This is how I started with. After extensive literature surveys in a particular interest area one is able to get a bigger picture on the subject matter and can identify potential problems which are yet to be solved/addressed. In that light one must go through review articles as well. Normally professors and scientists have a good idea and knowledge about potential problems in specific research areas. These problems, if properly addressed either theoretically or experimentally will lead to a well recognized research and can be published in reputed journals. Therefore I also advice students to interact with faculty as well other eminent scientists who often visit our institute for delivering lectures/workshops and try to discuss about such topics. Students should also try and attend conferences and national seminars on topics of their interest. This will give them an opportunity to closely interact with the leading scientists in the area and will also improve their awareness on the subject.
The most reputed journals are looking for research works which have either addressed persisting problems in a particular area or have discovered/devised/synthesized a completely new phenomena/device/substance. Moreover, a lot of major researches are getting multidisciplinary and group activities as mentioned before and thus a person with a particular background plays a very specific role in a project. One must be open to honest collaborations and partnerships for carrying out interdisciplinary research. The only difference between research in India and developed countries in Europe and USA is the scale of funding. Due to the large funding, more sophisticated instruments are affordable by a large number of institutions, giving them the technical advantage to perform the most difficult and sensitive experiments. Moreover the greater amount of funding attracts more intellectuals to these institutions and consequently they prosper. However, comparing by intellectual capital Indian scientists are at par with everyone else in the world.
Q-4: What is your career plan?
I do not plan to take to take up a job anytime soon and thus I have not participated in campus placements. Working with Prof. G. V. S. Sastry at my department and spending two summers at Rice University under Prof. Ajayan has inspired me to take up a research career. I am very thankful to my mentors who have always supported me and shown me the right direction. I have also learnt the value of hard work and the importance of ethics in the academic world from them. I have appeared for GRE and have applied to universities abroad for a PhD position. I mostly plan to join Prof. Ajayan’s group at Rice University as a PhD student. However I am trying my luck at other reputed universities like MIT, Caltech and Northwestern. Should anything work out at any of these places I may consider going to these universities. After PhD I don’t know what direction will my career take but as of now I am more inclined towards an academic career.
The experience at Rice University opened my mind to new areas and possibilities of carrying out research. It was a very inspiring experience which motivated me to go in-depth in the area of my interest. It also exposed me to the global publishing and academic scenario which is very different form what we see in India. At the same time my experiences with Prof. Sastry and Dr. Anchal at IT-BHU have taught me that in spite of resource limitations excellent research can be pursued if one has the right mindset, thinking and determination.
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Following is the links of publications which published paper of Deep Jariwala.
His original research paper on Atomic layers of hybridized boron nitride and graphene domains can be viewed here.
Nature materials-Atomic layers of hybridized boron nitride and graphene domains.pdfPublication Links:
http://www.sciencedaily.com/releases/2010/03/100301165740.htm
http://www.nanowerk.com/news/newsid=15110.php
http://www.media.rice.edu/media/NewsBot.asp?MODE=VIEW&ID=13823&SnID=99880918
http://www.zeenews.com/news607926.html
http://news.oneindia.in/2010/03/02/2d-graphene-quilt-offers-new-microelectronicpossibilities.html
http://www.azonano.com/news.asp?newsID=16224
http://www.physorg.com/news186682880.html
http://www.rdmag.com/News/Feeds/2010/03/environment-rice-researchers-make-graphene-hybrid/
http://www.eurekalert.org/pub_releases/2010-03/ru-rrm030110.php
http://www.sciencecodex.com/rice_researchers_make_graphene_hybrid
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Published article in Nature Materials, published on February 28, 2010
http://www.nature.com/nmat/journal/vaop/ncurrent/abs/nmat2711.html
Article abstract
Nature Materials
Published online: 28 February 2010 | doi:10.1038/nmat2711
Atomic layers of hybridized boron nitride and graphene domains
Lijie Ci1,6, Li Song1,6, Chuanhong Jin2, Deep Jariwala1,7, Dangxin Wu3, Yongjie Li1,7, Anchal Srivastava1,7, Z. F. Wang3, Kevin Storr4, Luis Balicas5, Feng Liu3 & Pulickel M. Ajayan1
Abstract
Two-dimensional materials, such as graphene and monolayer hexagonal BN (h-BN), are attractive for demonstrating fundamental physics in materials and potential applications in next-generation electronics. Atomic sheets containing hybridized bonds involving elements B, N and C over wide compositional ranges could result in new materials with properties complementary to those of graphene and h-BN, enabling a rich variety of electronic structures, properties and applications. Here we report the synthesis and characterization of large-area atomic layers of h-BNC material, consisting of hybridized, randomly distributed domains of h-BN and C phases with compositions ranging from pure BN to pure graphene. Our studies reveal that their structural features and bandgap are distinct from those of graphene, doped graphene and h-BN. This new form of hybrid h-BNC material enables the development of bandgap-engineered applications in electronics and optics and properties that are distinct from those of graphene and h-BN.
1. Department of Mechanical Engineering & Materials Science, Rice University, Houston, Texas 77005, USA
2. Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan
3. Department of Materials Science & Engineering, University of Utah, Salt Lake City, Utah 84112, USA
4. Department of Physics, Prairie View A&M University, Prairie View, Texas 77446, USA
5. National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
6. These authors contributed equally to this work
7. Present addresses: Department of Metallurgical Engineering, Banaras Hindu University, Varanasi 221005, India (D.J.); Department of Physics, Banaras Hindu University, Varanasi 221005, India (A.S.); Department of Chemistry, Lanzhou University, Lanzhou 730000, China (Y.L.)
Correspondence to: Pulickel M. Ajayan1 e-mail: ajayan@rice.edu
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Published article in Printed Electronics World, published on March 02, 2010
2 March 2010
Country: United States
Rice researchers make graphene hybrid
One-atom-thick sheet offers new microelectronic possibilities
Rice University researchers have found a way to stitch graphene and hexagonal boron nitride (h-BN) into a two-dimensional quilt that offers new paths of exploration for materials scientists.
The technique has implications for application of graphene materials in microelectronics that scale well below the limitations of silicon determined by Moore's Law.
New research from the lab of Pulickel Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science and of chemistry, demonstrates a way to achieve fine control in the creation of such hybrid, 2-D structures.
Layers of h-BN a single atom thick have the same lattice structure as graphene, but electrically the materials are at opposite ends of the spectrum: h-BN is an insulator, whereas graphene, the single-atom-layer form of carbon, is highly conductive. The ability to assemble them into a single lattice could lead to a rich variety of 2-D structures with electric properties ranging from metallic conductor to semiconductor to insulator.
Because graphene is a conductor and h-BN is an insulator, the proportion of one to the other determines how well this new material conducts electrons. Lijie Ci and Li Song, both postdoctoral research scientists in Ajayan's lab, found that by putting down domains of h-BN and carbon via chemical vapor deposition (CVD), they were able to control the ratio of materials in the film that resulted.
Ci and Song are primary authors of a paper about the work that appeared in the online edition of Nature Materials this week. Ajayan said the discovery is thrilling for a materials scientist.
"From a graphene perspective, it now gives us an opportunity to explore band-gap engineering in two-dimensional layered systems," he said. "The whole phase diagram of boron, carbon and nitrogen is fascinating, unexplored and offers a great playground for materials scientists. This is only the first instance showing that these structures can indeed be grown in 2-D like graphene," Ajayan said. "I think the whole new field will be exciting for basic physics and electro-optical applications."
Graphene has been the subject of intense study in recent years for its high conductivity and the possibility of manipulating it on scales that go well below the theoretical limits for silicon circuitry. A layer of graphene is a hexagonal lattice of carbon atoms. In bulk, it's called graphite, the stuff of pencil lead. Graphene was first isolated in 2004 by British scientists who used Scotch tape to pull single-atom layers from graphite.
"Graphene is a very hot material right now," said Song, who had teamed with Ci to investigate doping graphene with various materials to determine its semiconducting properties. Knowing that both boron and nitrogen had already been used in doping bulk graphite, they decided to try cooking it via CVD onto a copper base.
Structurally, h-BN is the same as graphene, a hexagon-shaped lattice of carbon atoms that looks like chicken wire. Ci and Song found that through CVD, graphene and h-BN merged into a single atomic sheet, with pools of h-BN breaking up the carbon matrix.
The critical factor for electronic materials is the band gap, which must be tuned in a controlled manner for applications. Graphene is a zero-gap material, but ways have been proposed to tailor this gap by patterning it into nanoscale strips and doping it with other elements.
Ci and Song took a different approach through CVD, controlling the ratio of carbon to h-BN over a large, useful range.
It remains challenging to produce single layers of the hybrid material, as most lab-grown films contain two or three layers. The researchers also cannot yet control the placement of h-BN pools in a single sheet or the rotational angles between layers - but they're working on it.
In fact, having multiple layers of the hybrid at various angles creates even more possibilities, they said. "For pure graphene, this rotation will affect the electronic properties," said Ci, who moved with Ajayan's lab from Rensselaer Polytechnic Institute to Houston in 2007.
The researchers are considering producing these materials on industrial-scale wafers. Graphene sheets several inches wide have already been synthesized in other labs, Ci said. And because graphene can be lithographically patterned and cut into shapes, the new material has great potential to be fabricated into useful devices with controllable electrical properties.
Co-authors on the paper with Ci, Song and Ajayan are visiting students Deep Jariwala and Yongjie Li and visiting professor Anchal Srivastava, all at Rice; Chuanhong Jin of the Nanotube Research Center, National Institute of Advanced Industrial Science and Technology in Tsukuba, Japan; Dangxin Wu, Z.F. Wang and Feng Liu of the Department of Materials Science and Engineering at the University of Utah; Kevin Storr of the Department of Physics at Prairie View A&M University; and Luis Balicas of the National High Magnetic Field Laboratory in Tallahassee, Fla.
Funding for the research came from Rice, the Office of Naval Research's Multidisciplinary University Research Initiative program on graphene and the Basic Energy Sciences Division of the Department of Energy.
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Deep Jariwala in Chronicle October 2009 issue:
Summer Internship abroad-First Hand Report
http://www.itbhuglobal.org/chronicle/archives/2009/10/summer_internsh_1.php
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(if you having troubles, try posting your comment on this page or send an email to chronicle @ itbhuglobal.org)Institute of Technology, Banaras Hindu University
Varanasi 221005, UP