Thalappil Pradeep | |
---|---|
Nationality | Indian |
Alma mater | Indian Institute of Science, Bangalore, University of California, Berkeley, Purdue University, West Lafayette |
Awards | Eni Award (2023), VinFuture Prize (2022), Prince Sultan bin Abdulaziz International Prize for Water (2022), Padma Shri (2020), Nikkei Asia Prize (2020), TWAS Prize (2018), Shanti Swarup Bhatnagar Prize (2008) |
Scientific career | |
Fields | Molecular materials and surfaces |
Institutions | Indian Institute of Technology Madras |
Website | https://pradeepresearch.org/ |
Thalappil Pradeep [1] is an institute professor and professor of chemistry in the Department of Chemistry at the Indian Institute of Technology Madras. He is also the Deepak Parekh Chair Professor. In 2020 he received the Padma Shri award for his distinguished work in the field of Science and Technology. [2] He has received the Nikkei Asia Prize (2020), The World Academy of Sciences (TWAS) prize (2018), and the Shanti Swarup Bhatnagar Prize for Science and Technology in 2008 by Council of Scientific and Industrial Research. [3] [4]
Pradeep was born on July 8, 1963, at Panthavoor, Kerala, India, to (late) Thalappil Narayanan Nair and Pulakkat Panampattavalappil Kunjilakshmi Amma. Both his parents were school teachers. His father was a writer too, with the pen name N. N. Thalappil, who authored 14 books in Malayalam.
Pradeep was educated in government schools all through. From 5th to 10th, he was educated at the Govt. High School, Mookkuthala where his father taught Malayalam and mother taught social studies. The school was built by Shri. Pakaravoor Chitran Namboothiripad, who donated it to the Government at a token price of Rs. 1. Most of the days he walked the 4 km trip to the school, as most of his classmates. Later, he was educated at the MES College, Ponnani for his Pre Degree, St. Thomas College, Thrissur for his BSc and Farook College, Kozhikode for his MSc, all under Calicut University.
Pradeep [5] earned a PhD degree in chemical physics working with Professors C. N. R. Rao [6] and M. S. Hegde at the Indian Institute of Science, Bangalore during 1986–91. [7] Subsequently, he spent about two years as a post-doctoral fellow at the University of California, Berkeley [8] with Prof. David A. Shirley and Purdue University, Indiana with Prof. R. Graham Cooks. [9] Since then, he has been working at the Indian Institute of Technology Madras, [10] where he is an institute professor. He held visiting positions at Purdue University, [9] Leiden University, in the Netherlands, [11] EPFL, Switzerland, [12] the Institute of Chemistry, Taiwan, [13] Pohang University of Science and Technology, South Korea [14] and the University of Hyogo, Japan. [15]
Pradeep's work is in the area of molecular materials and surfaces. The materials and phenomena he discovered have implications to clean environment, affordable clean water and ultrasensitive devices. Some of his discoveries have been translated to viable products and several of his recent findings [16] have immense scope for the benefit of the world at large and developing world in particular. Along with such studies, he pursued fundamental problems of relevance to the science of ice surfaces. [17] For studies of ultrathin surfaces of molecular solids such as ices, he developed unique instrumentation, [18] an important aspect of his research.
Pradeep discovered several atomically precise clusters or nano molecules of noble metals. These are molecules composed of a few atom cores, protected with ligands, especially thiols which are fundamentally different from their bulk and plasmonic analogues in terms of their optical, electronic, and structural properties. Such clusters show distinct absorption spectra and well-defined luminescence, mostly in the visible and near-infrared regions, just as molecules. He introduced several new synthetic approaches to make new clusters (a summary of the methods is presented in reference [19] ), showed some of the first examples of chemistry with such materials and developed applications with them. Most recent of these examples is the introduction of inter-cluster reactions between clusters, [20] which demonstrate that nanoparticles behave like simple molecules and stoichiometric reactions of the type, A + B → C + D, can be written for these processes, where A, B, C and D are nanoparticles. To describe the structure and properties of such clusters, his group has introduced a system of nomenclature for such systems in general. [21] This kind of chemistry performed with isotopically pure nanoparticles of the same metal has shown that metal atoms in nanoparticles undergo rapid exchange in solution as in the case of water. [22]
The important atomically precise clusters he discovered are: Ag7/8, [23] Ag9, [24] Au23, [25] Ag152 [26] and the smallest molecular alloy, Ag7Au6. [27] He created methods to form highly uniform nanotriangles [28] and introduced a new family of materials called mesoflowers. [29] Combining luminescent atomically precise clusters with mesoflowers and nanofibres, he developed sensors at sub-zeptomole levels [30] which are probably the limits of fast molecular detection. A single mesoflower has been shown to detect nine molecules of trinitrotoluene (TNT). A recent example of this chemistry is the detection of 80 ions of Hg2+ with single nanofibers. [31] A number of atomically precise luminescent clusters have been made in proteins and their growth involves inter-protein metal transfer. [32] These clusters were shown to be excellent biolabels. [33] Early examples of cluster functionalisation [34] were demonstrated by him and the methods he introduced are shown to impart properties such as fluorescence resonance energy transfer to such systems [35] and these methodologies are now used for applications. Cluster functionalisation chemistry has recently been extended to make isomers of nanomolecules and these have been isolated in collaboration with Japanese scientists. [36] He has recently demonstrated supramolecular functionalisation of clusters. [37] Such clusters help assemble 1D nanostructures, leading to precise 3D structures. [38]
Simple methods of synthesis and analysis have been some of the focal themes of his research. In a recent work, molecular ionization was demonstrated at 1 V from a carbon nanotubes-impregnated paper. [39] This methodology was used to collect high quality mass spectra of diverse analytes. Besides the advantage of low internal energy of the ions, which preserves fragile species and intermediates, the methodology helps in miniaturising mass spectrometry. Ion-based chemistry is now used to synthesise structures such as metal grasslands, extending over cm2 areas. [40]
He discovered noble metal nanoparticle-based drinking water purification methods [41] [42] [43] and developed the world's first drinking water filters utilising nanochemistry. The chemistry he developed was reductive dehalogenation of halocarbons at noble metal nanoparticle surfaces which when applied to several of the common pesticides present in surface waters of India, resulted in their degradation at room temperature and extremely low concentrations, of the order of parts per billion. The process when occurs on supported nanoparticles, trace concentrations of halocarbon pesticides can be removed from a flowing water stream. Water purifiers based on this technology have been introduced in the market since 2007. As a result of this innovation, many activities have started in India and elsewhere and we are now certain of the impact of nanomaterials in clean water. [44] About 1.5 million of these filters have been sold in the market till 2016. IIT Madras received over Rs. 230 lakhs in royalties from this finding, the first of its kind in the Indian university system, in terms of royalty earnings and reach from a single patent.
He developed several new technologies in the recent past to tackle various other contaminants such as arsenic, lead, mercury and organics in water, which are the subject of a few issued and filed patents. Such capabilities to bring contaminant concentrations under drinking water norms using diverse nanomaterials, feasible synthesis of such materials in quantities, creation of viable processes for their implementation along with the use of efficient sensors would make clean drinking water affordable using nanomaterials. [45] A critical problem in achieving this goal is the development of advanced and affordable materials with no or reduced environmental impact. Some of the materials and technologies he has developed over the years have been combined to make affordable all-inclusive point-of-use drinking water purifiers, [16] which are being installed in various parts of the country, both as a community and as domestic units. These advanced sand-like composites are made in the water at room temperature, with no environmental cost. [46] [47] Gravity-fed water solutions using such materials without the use of electricity can make sustainable access to safe drinking water a reality.
With all these developments, ‘nanomaterials for water purification’ is recognised as one of the major themes of research in the area. Pradeep has shown that completely home-grown nanotechnology, from lab to market is possible in India. His recent discovery of ultrasensitive single-particle sensors with the capacity to detect a few tens of molecules and ions [30] [31] may be combined with new materials to make simultaneous sensing and scavenging at ultra-trace levels possible. The new materials he has developed have been put together to make community purifiers in arsenic affected areas of West Bengal which have been running for seven years. Arsenic-free water is now being delivered to about 10,00,000 people using these technologies. The technology has now been approved for national implementation.
He created 3D organised structures of nanoparticles called superlattices [48] and used them for surface enhanced Raman imaging [49] [50] and specific gas sensing applications. [51]
In his earlier research, Pradeep discovered that binding of metallic nanoparticles on metallic carbon nanotube bundles made the latter semiconducting and consequently the nanoparticle-nanotube composite became luminescent in the visible region. [52] This luminescence was reversible by the exposure of specific gases such as hydrogen as they occupied the interstitial sites of the bundle. He showed a transverse electrokinetic effect in metal nanoparticle assemblies which resulted in a potential when a liquid was flown over it. [53] [54] Using spectroscopic and scattering techniques, he showed that long chain monolayers on metal nanoparticle surfaces were rotationally frozen. [55] [56] This is in contrast to the monolayers on planar surfaces, which are in a rotator phase at room temperature (RT). All of these results have implications to the applications of nanoparticles in diverse areas.
Other aspect of his research is on ice, the solid form of water. He found novel processes occurring at the very top of ice surfaces which are of particular relevance to atmospheric chemistry. Among the various examples, he has shown that the vapour pressures of gases oscillate over melting ice; [57] the study has implications to the fundamental understanding of dynamics of gas phase over condensed systems. He showed that the elementary reaction, H+ + H2O → H3O+ in the gas phase and in liquid water happens differently on ice surfaces, namely one channel follows, H+ + H2O (ice) → H2+ + OH.(ice), when H+ collides ice at ultra low kinetic energies. [58] In other words, while H+ makes hydronium ion in liquid water, it results in dihydrogen cation on ice. He showed that molecular transport of even slightly different molecules is largely different within ice. [59] To discover and understand such processes, especially at the very top of ice, he built the very first ultra low energy (1-10 eV) ion scattering spectrometer, a new tool in extremely surface sensitive spectroscopy, working at cryogenic temperatures as in space. [18] In this experiment, mass and energy selected ions undergo collisions at ultra-thin molecular surfaces prepared on single crystals and the product ions are studied by a mass spectrometer. The surfaces are simultaneously characterized by a range of techniques such as reflection-absorption infrared spectroscopy and secondary ion mass spectrometry. Using this infrastructure the group has shown that methane hydrate can exist in ultrahigh vacuum and at ultra-cold conditions as in interstellar space. [60]
The current research group [61] is a mix of diverse expertise. The group members are largely chemists along with some chemical engineers, physicists, computer science graduates, biologists and instrumentation engineers. The group has almost all the tools required for advanced materials science within itself. Other facilities are available in the institute. There are also intense collaborations with scientists across the world.
He has taught undergraduate and graduate-level courses at IITM for over 25 years and trained over 250 students at various levels to conduct research, including 45 completed and 30 ongoing PhDs, 110 MSc/MTech theses, 40 postdocs and several visiting students from India and abroad.
Five companies have been incubated.
1. InnoNano Research Pvt. Ltd. (a start-up company at IIT Madras). Not operational currently.
2. Innodi Water Technologies Pvt. Ltd. [66] (incubated at IIT Madras Incubation Cell). InnoDI (inno-dee-eye) develops and builds Capacitive De-ionization (CDI) based water treatment systems for the Indian and international market and has established manufacturing facilities.
3. VayuJal Technologies Pvt. Ltd. [67] (incubated at IIT Madras Incubation Cell). Vayujal develops power-efficient atmospheric water generators.
4. AquEasy Innovations Pvt. Ltd. (incubated at IIT Madras Incubation Cell). AquEasy makes an affordable, point of use drinking water purification technologies.
5. Hydromaterials Pvt. Ltd. (incubated at IIT Madras Incubation Cell). Hydromaterials uses new materials for clean water.
These technologies have delivered clean water to 10 million people.
Several other patents have been licensed.
Conceptualised and built state of the art centres for advanced research and technology development, Thematic Unit of Excellence [68] was built for developing new technologies in the water sector.
To build such technologies with the participation of the global community, a new centre called the International Centre for Clean Water (ICCW) [69] was built at the IIT Madras Research Park. [70]
1. T. Pradeep, Nano: The Essentials Understanding Nanoscience and Nanotechnology, Tata McGraw-Hill, New Delhi, 2007, reprinted 2008, 2009, 2010 (twice), 2011, 2012, 2014, 2015, 2015, 2016, 2017, 2018, 2019 and 2020.
2. S. K. Das, S. U. S. Choi, W. Yu, T. Pradeep, Nanofluids Science and Technology, John Wiley, New York (2008).
3. Nano: The Essentials Understanding Nanoscience and Nanotechnology, McGraw-Hill, April 2008. (International edition).
4. Nano: The Essentials Understanding Nanoscience and Nanotechnology, in Japanese, Kyorisu Press, August 2011.
5. T. Pradeep and others, A Textbook on Nanoscience and Nanotechnology, McGraw-Hill Education, New Delhi 2012. (This book is now a textbook in several universities for advanced nanoscience and nanotechnology courses). Reprinted 2014.
6. David E. Reisner and T. Pradeep (Eds.), Aquananotechnology: Global Prospects, CRC Press, New York, 2015.
7. T. Pradeep (Ed.), Atomically Precise Metal Nanoclusters, Elsevier, October 2022.
There are several books in which his articles are included.
A few are below:
1. Detection and extraction of pesticides from drinking water using nanotechnologies, T. Pradeep and Anshup, in Nanotechnology applications for clean water N. Savage, M. Diallo, J. Duncan, A. Street and R. Sustich (Ed), William Andrew, New York, 2008.
2. Gold nanoparticles, P. R. Sajanlal and T. Pradeep, Kirk-Othmer Encyclopedia (2011).
3. Noble metal nanoparticles, T. S. Sreeprasad and T. Pradeep, Springer Handbook of Nanomaterials, R. Vajtai (Ed.), Springer, Heidelberg, 2013. [71]
4. Noble metal clusters in protein templates, T. Pradeep, A. Baksi and P. L. Xavier in Functional nanometer-sized clusters of transition metals: Synthesis, properties and applications, W. Chen and S. Chen (Ed.), RSC Publishing, London, 2014.
5. Detection and extraction of pesticides from drinking water using nanotechnologies (Second Edition), T. Pradeep, Anshup and M. S. Bootharaju, in Nanotechnology applications for clean water [72] A. Street, R. Sustich, J. Duncan and N. Savage (Ed.), Elsevier, 2014.
1. ‘Vipathinte Kalochakal’, T. Pradeep, National Book Stall, Kottayam, 1990.
2. ‘Aanava Prathisandhi’ T. Pradeep and K. Vijayamohanan, DC Books, Kottayam, 1991.
3. Chapter in, “Anusakthi Aapathu”, Ed. RVG Menon, Sugathakumari, 1991.
4. “Kunjukanangalku Vasantham Nanotechnologikku Oramukham”, DC Books, Kottayam, 2007. This is based on a series of articles in Mathrubhumi Illustrated Weekly published during 2006–2007. (Won the Kerala Sahitya Academi Award of 2010)
5. Chapter in, Rasathanthram: Jeevithavum Bhavium (translated as Chemistry: Life and Future), Kerala Sastra Sahitya Parishad, Trissur, 2011.
There are several popular science articles in English and Malayalam.
Pradeep is a Fellow of the Indian National Science Academy, Indian Academy of Sciences, Indian National Academy of Engineering, The National Academy of Sciences, The Royal Society of Chemistry, The American Association for the Advancement of Science, and The World Academy of Sciences. He has received the lifetime achievement research award of Indian Institute of Technology, Madras and is designated as an Institute Professor.
He is Associate Editor of the journal, ACS Sustainable Chemistry & Engineering, 2014-. Editorial Boards: Asian Journal of Spectroscopy, 2000-; Oriental Journal of Chemistry, 2000-; Nano Reviews, 2010- ACS Applied Materials and Interfaces, 2012–2015; Particle, 2012-; Surface Innovations, 2012-; Nanoscale, 2014-; Chemistry – An Asian Journal, 2014-; Scientific Reports (Nature Group), 2015-; International Journal of Water and Wastewater Treatment, 2015-; Chemistry of Materials, 2018-; ACS Nano, 2018-; Nanoscale Advances, 2019-; Analytical Chemistry, 2020-.
Pradeep has been advocating the use of noble metal-based nanotechnology for purifying the environment. [44] 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. Such technologies have to combine with many others for a sustainable society. Several such pointers are suggested. [45]
Nanotechnology was defined by the National Nanotechnology Initiative as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). At this scale, commonly known as the nanoscale, surface area and quantum mechanical effects become important in describing properties of matter. The definition of nanotechnology is inclusive of all types of research and technologies that deal with these special properties. It is therefore common to see the plural form "nanotechnologies" as well as "nanoscale technologies" to refer to the broad range of research and applications whose common trait is size. An earlier description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology.
Molecular engineering is an emerging field of study concerned with the design and testing of molecular properties, behavior and interactions in order to assemble better materials, systems, and processes for specific functions. This approach, in which observable properties of a macroscopic system are influenced by direct alteration of a molecular structure, falls into the broader category of “bottom-up” design.
Nanomaterials describe, in principle, materials of which a single unit is sized between 1 and 100 nm.
Colloidal gold is a sol or colloidal suspension of nanoparticles of gold in a fluid, usually water. The colloid is coloured usually either wine red or blue-purple . Due to their optical, electronic, and molecular-recognition properties, gold nanoparticles are the subject of substantial research, with many potential or promised applications in a wide variety of areas, including electron microscopy, electronics, nanotechnology, materials science, and biomedicine.
A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead.
James Mitchell Tour is an American chemist and nanotechnologist. He is a Professor of Chemistry, Professor of Materials Science and Nanoengineering at Rice University in Houston, Texas.
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As the world's energy demand continues to grow, the development of more efficient and sustainable technologies for generating and storing energy is becoming increasingly important. According to Dr. Wade Adams from Rice University, energy will be the most pressing problem facing humanity in the next 50 years and nanotechnology has potential to solve this issue. Nanotechnology, a relatively new field of science and engineering, has shown promise to have a significant impact on the energy industry. Nanotechnology is defined as any technology that contains particles with one dimension under 100 nanometers in length. For scale, a single virus particle is about 100 nanometers wide.
Green nanotechnology refers to the use of nanotechnology to enhance the environmental sustainability of processes producing negative externalities. It also refers to the use of the products of nanotechnology to enhance sustainability. It includes making green nano-products and using nano-products in support of sustainability.
Nanomaterials can be both incidental and engineered. Engineered nanomaterials (ENMs) are nanoparticles that are made for use, are defined as materials with dimensions between 1 and 100nm, for example in cosmetics or pharmaceuticals like zinc oxide and TiO2 as well as microplastics. Incidental nanomaterials are found from sources such as cigarette smoke and building demolition. Engineered nanoparticles have become increasingly important for many applications in consumer and industrial products, which has resulted in an increased presence in the environment. This proliferation has instigated a growing body of research into the effects of nanoparticles on the environment. Natural nanoparticles include particles from natural processes like dust storms, volcanic eruptions, forest fires, and ocean water evaporation.
Nanodiamonds, or diamond nanoparticles, are diamonds with a size below 100 nanometers. They can be produced by impact events such as an explosion or meteoritic impacts. Because of their inexpensive, large-scale synthesis, potential for surface functionalization, and high biocompatibility, nanodiamonds are widely investigated as a potential material in biological and electronic applications and quantum engineering.
Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. While frequently described as being 'silver' some are composed of a large percentage of silver oxide due to their large ratio of surface to bulk silver atoms. Numerous shapes of nanoparticles can be constructed depending on the application at hand. Commonly used silver nanoparticles are spherical, but diamond, octagonal, and thin sheets are also common.
Nanofluidic circuitry is a nanotechnology aiming for control of fluids in nanometer scale. Due to the effect of an electrical double layer within the fluid channel, the behavior of nanofluid is observed to be significantly different compared with its microfluidic counterparts. Its typical characteristic dimensions fall within the range of 1–100 nm. At least one dimension of the structure is in nanoscopic scale. Phenomena of fluids in nano-scale structure are discovered to be of different properties in electrochemistry and fluid dynamics.
Nanoparticles are classified as having at least one of its dimensions in the range of 1-100 nanometers (nm). The small size of nanoparticles allows them to have unique characteristics which may not be possible on the macro-scale. Self-assembly is the spontaneous organization of smaller subunits to form larger, well-organized patterns. For nanoparticles, this spontaneous assembly is a consequence of interactions between the particles aimed at achieving a thermodynamic equilibrium and reducing the system’s free energy. The thermodynamics definition of self-assembly was introduced by Professor Nicholas A. Kotov. He describes self-assembly as a process where components of the system acquire non-random spatial distribution with respect to each other and the boundaries of the system. This definition allows one to account for mass and energy fluxes taking place in the self-assembly processes.
Nanoclusters are atomically precise, crystalline materials most often existing on the 0-2 nanometer scale. They are often considered kinetically stable intermediates that form during the synthesis of comparatively larger materials such as semiconductor and metallic nanocrystals. The majority of research conducted to study nanoclusters has focused on characterizing their crystal structures and understanding their role in the nucleation and growth mechanisms of larger materials.
In materials and electric battery research, cobalt oxide nanoparticles usually refers to particles of cobalt(II,III) oxide Co
3O
4 of nanometer size, with various shapes and crystal structures.
Lithium–silicon batteries are lithium-ion battery that employ a silicon-based anode and lithium ions as the charge carriers. Silicon based materials generally have a much larger specific capacity, for example 3600 mAh/g for pristine silicon, relative to the standard anode material graphite, which is limited to a maximum theoretical capacity of 372 mAh/g for the fully lithiated state LiC6.
Virus nanotechnology is the use of viruses as a source of nanoparticles for biomedical purposes. Viruses are made up of a genome and a capsid; and some viruses are enveloped. Most virus capsids measure between 20-500 nm in diameter. Because of their nanometer size dimensions, viruses have been considered as naturally occurring nanoparticles. Virus nanoparticles have been subject to the nanoscience and nanoengineering disciplines. Viruses can be regarded as prefabricated nanoparticles. Many different viruses have been studied for various applications in nanotechnology: for example, mammalian viruses are being developed as vectors for gene delivery, and bacteriophages and plant viruses have been used in drug delivery and imaging applications as well as in vaccines and immunotherapy intervention.
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