Dr Amol Kulkarni explaining the technology to DG, CSIR
CSIR-National Chemical Laboratory (NCL), Pune has developed the world’s most inexpensive technology for continuous large scale production of precision silver nanowires on a large scale. Dr Shekhar C. Mande, Director-General, CSIR, inaugurated the pilot plant for continuous flow manufacture of Silver Nanowires at the CSIR-NCL campus.
The technology has been developed by a team led by Dr Amol A. Kulkarni from the Chemical Engineering and Process Development Division. This technology development was carried out under the Advanced Manufacturing Technologies (AMT) initiative by the Department of Science and Technology (DST).
Globally, nanomaterials are being synthesised for the last three decades and specifically in the form of utilisable entities over the last 15 years. Metal and metal oxide nanomaterials show wonderful properties that are different from the bulk form.
Currently, more than 99% of the manufacturers of these materials are outside India. In general, India imports most of the nanomaterials (except a few inorganic oxides viz. TiO2 and carbon nanomaterials). The manufacturers have evolved rapidly while developing various technologies that never existed before (viz. metal mesh technology for multi-touch screen, filters for optical components, polymer-nano composites for coatings, printable circuits, nanoceramic dental implants having antimicrobial surface coatings, nano-diaphragms for acoustic sensing, accurate diagnosis, etc.).
In recent times, silver nanowires have caught attention due to their suitability for printed and flexible electronics. They find use in tightly controlled markets (viz. touch screen, conducting inks, thermal coatings, IR shielding sector, etc.) where India has almost zero footprint. Now, with this technology developed at CSIR-NCL, Indian industries will be able to enter into manufacturing of this precision material. Patents have been filed to protect the technology and the product has been tested for various applications including conducting inks in various forms.
Dr Amol Kulkarni’s team comprising Ms Prachi Kate and Ms Suneha Patil was upbeat about the successful development of this scalable process. The other scientists involved in the team Dr B.L.V. Prasad and Dr Nandini Devi also contributed to this challenging interdisciplinary work. CSIR-NCL has already signed a material transfer agreement with an Indian company Nanorbital Advanced Materials Pvt. Ltd and another is in progress. The technology is available for licensing.
The silver nanowire market size was over USD 295 million in 2018. On the flipside, large-scale production of these nanowires is a stumbling block in the growth of the market studied. The pilot plant at CSIR-NCL can produce as much as 500 gm/day and is scalable to any desired production rates thereby removing these stumbling blocks. The price for the silver nanowires of different sizes (20 nm to 100 nm diametre) varies from 250 USD to 600 USD per gram. The silver nanowires produced from this technology are at least 12 times cheaper than the global rates. The process is tuneable to manufacture a wide range of nanowires suitable for a variety of applications.
Starting with this technology as a seed point, CSIR-NCL aims to develop more such precision technologies that would help Indian industries to enter into the domain of extremely high-value electronic chemicals.
On this occasion, Dr Mande said, “The global market for Silver Nanowires is very large. In India there is no manufacturer for this; hence it is an opportunity for the Indian manufacturers to come up as it has huge potential. With this, the CSIR will proactively enter this large space of long term relevance.”
Dr Kulkarni said, “The method of synthesis is known chemistry but it was possible using different control parameters in the lab. The purpose was to create a technology that will compete in the world and get into the field of electrical chemicals.”