Nanotechnology

Nanotechnology, tracing its origins to the study of nanoparticles in the mid-19th century, has seen significant advancements driven by key figures like Faraday, Feynman, and Taniguchi. It operates on bottom-up and top-down approaches, offering unique methods for material construction. Nanomaterials exhibit distinct properties such as strength, conductivity, and reactivity, making them invaluable across various sectors. Government initiatives like the Nano Mission and INUP-i2i have propelled nanotechnology research in India. However, challenges including health risks, environmental impact, and ethical considerations persist. Despite this, the potential of nanotechnology to address societal needs and drive economic growth remains significant, necessitating continued investment and responsible innovation in India.

Nanoparticles, which serve as the building blocks for various products in nanotechnology, began to be studied in the mid-19th century, despite their widespread use in today's technology. A significant advancement in nanotechnology occurred in 1857 when Michael Faraday conducted experiments with aqueous colloidal solutions containing small gold nanoparticles, investigating their optical and electrical properties. The size of nanoparticles was first accurately measured by Richard Zsigmondy in 1925, leading to the introduction of the concept of nanometers. Richard Feynman, in 1959, in his lecture titled "There's Plenty of Room at the Bottom", proposed the possibility of manipulating matter at atomic and molecular scales through specialized measurement and production techniques, laying the foundation for nanotechnology. Often credited as the pioneer of nanotechnology, Norio Taniguchi coined the term in 1974, defining it as processes involving the manipulation, separation, joining, and deformation of materials at the atomic or molecular level. Eric Drexler played a crucial role in popularizing nanotechnology and raising awareness about its potential benefits and risks through his publications. The invention of the Scanning Tunneling Microscope by Gerd Binnig and Heinrich Rohrer in 1981, and the development of the atomic force microscope by Gerd Binnig, Calvin Quate, and Christoph Gerber in 1986, were significant milestones that propelled the advancement of nanotechnology.

The term 'nano' originates from the Latin word for 'dwarf' and is utilized in scientific contexts to denote a nanometer (nm). A nanometer is one-billionth of a meter, equivalent to a millionth of a millimeter. To put it into perspective, a single human hair typically measures around 80,000 nanometers in width. Nanotechnology encompasses the interdisciplinary fields of science, engineering, and technology at the nanoscale, which typically ranges from 1 to 100 nanometers. At this scale, materials exhibit unique properties and behaviors that differ from those observed in bulk materials. For instance, characteristics such as melting point, color, strength, and chemical reactivity may undergo significant changes at the nanoscale.

Innovations in nanotechnology are crucial for maintaining leadership positions in industries such as semiconductors and strategic computing. Moreover, nanotechnology advancements are vital for addressing various national priorities, including space exploration, energy production, medical treatment, agricultural practices, and national security.

Nanomaterials possess distinctive properties that set them apart from bulk materials:

• Strength and Lightness: Nanomaterials can be stronger and lighter, making them ideal for aerospace and structural applications.
• Conductivity: They conduct heat or electricity differently due to their high surface area-to-volume ratio, benefiting electronics and energy technologies.
• Color Variability: Nanoparticles like gold can change color based on size and shape, useful in sensing and imaging applications.
• Transparency and Catalysis: Opaque materials like copper can become transparent, while inert ones like platinum can act as efficient catalysts at the nanoscale.
• Chemical Reactivity: Stable materials like aluminum can become highly reactive and combustible, offering new possibilities in energy storage.
• Phase Transition: Nanomaterials may transition between solid and liquid states at room temperature, enabling applications in lubrication and sensing.
• Conductivity of Insulators: Nanotechnology can turn insulators like silicon into conductors, crucial for modern electronics.

Nanotechnology employs two primary methodologies:

• Bottom-up approach: it involves constructing materials and devices by self-assembling molecular components through chemical processes guided by principles of molecular recognition.
• Top-down approach: It entails building nano-objects from larger entities without precise control at the atomic level.

Materials exhibit different behaviors at the nanoscale due to two main factors.

• Firstly, the increased surface area of very small particles compared to larger masses of the same material enhances their reactivity in chemical processes. For instance, salt grains dissolve much faster in water than a solid block of salt due to their larger surface area. Additionally, some materials that are typically inert in larger forms may display increased reactivity at the nanoscale.
• Secondly, at the nanoscale, the relative significance of various physical laws, including quantum effects, becomes more pronounced. These effects, which are often negligible at larger scales, become significant, particularly for particles smaller than 20 nanometers.

Following rapidly growing list of benefits and applications of nanotechnology make it as one of the key technologies of the 21st century:

1. Advancements in Agriculture:
   • Nanoporous zeolites and nanocapsules are utilized to improve the efficiency of water and fertilizer application, leading to enhanced plant growth. For instance, IFFCO introduced the world's first Liquid Nano urea, which reduces fertilizer usage while minimizing environmental pollution and the need for imports.
   • Nanosensors monitor soil quality and plant health in real-time, enabling proactive agricultural management.
   • Nanomagnets aid in the removal of soil contaminants, promoting a healthy agricultural ecosystem.
   • Nanosensors offer sensitive detection capabilities for pests, enabling effective intervention measures.
   • Nanoparticles contribute to the development of novel pesticides and insect repellents, promoting agricultural sustainability.
2. Health Care
   • Nanotubes and nanoparticles enable monitoring of vital parameters, promoting proactive healthcare management.
   • Nanoliter systems and nanosensor arrays provide advanced capabilities for precise disease diagnosis. For example, in the diagnosis of infections and cancers, antibodies are affixed to carbon nanotubes, enabling the detection of cancer cells in the bloodstream with high accuracy.
   • Quantum dots and magnetic nanoparticles enhance disease detection sensitivity.
   • Aid in Drug Delivery:
     1. The biodegradability of carbon nanotubes enables their potential use as carriers for drugs and antigens within the human body.
     2. Scientists at IISER, Thiruvananthapuram, have developed a novel three-component nanodrug delivery system aimed at mitigating the adverse effects of chemotherapy in cancer patients
     3. Nanocapsules, liposomes, and dendrimers enable controlled and sustained drug release.
3. Breakthroughs in Water Treatment:
   • Nanomembranes and nanosensors purify water, detect contaminants, and enable timely remediation measures.
   • Titanium dioxide nanoparticles catalyze the degradation of water pollutants, contributing to cleaner water resources.
4. Innovations in Energy:
   • Quantum dots enhance photovoltaic cells and organic light-emitting devices for efficient energy generation.
   • Carbon nanotubes in composite film coatings has revolutionised solar cell technology.
   • Nanocatalysts drive advancements in hydrogen generation for clean energy solutions.
   • Scientists from IIT-Kharagpur designed “Piezoelectric Nanogenerators” that can produce electricity through body movement like walking , speaking etc
5. Electronic Applications:
   • Significant size reduction of electronic components like nano transistors, processors, and storage devices has led to the development of compact and highly efficient devices such as smartphones and computers.
   • Computer chips now incorporate nano-sized features on their surfaces, facilitated by nanotechnology, resulting in enhanced speed and reduced size of computers.
   • Nano-scale wires and tubes exhibit exceptional optical, electronic, and magnetic characteristics, making them valuable for data storage in computer systems.
6. Enhanced Food Processing:
   • Nanocomposites and antimicrobial nanoemulsions improve food packaging and decontamination.
   • Nanotechnology-based biosensors enable rapid detection of pathogens in food products.
7. Combating Air Pollution:
   • Titanium dioxide nanoparticle-based systems and nanocatalysts remove air pollutants and reduce emissions.
   • Nanosensors detect toxic materials and leaks, facilitating proactive air quality management.
8. Advances in Construction Materials:
   • Nanomolecular structures and heat-resistant nanomaterials enhance durability and sustainability.
   • Self-cleaning surfaces with bioactive coatings reduce maintenance requirements.
9. Manufacturing Innovations :
   • Sports Equipments: Carbon nanotubes and graphene, among other nanomaterials, are integrated into the badminton racket frames, resulting in improved performance, increased durability, and enhanced player experience on the court.
   • Textile:
     1. Nanoparticles are integrated into textile fibers to provide durable wrinkle resistance, reducing the need for ironing and enhancing garment longevity.
     2. Antibacterial nanoparticles, such as silver nanoparticles, are embedded in textiles to inhibit microbial growth, making them ideal for applications in healthcare, sports, and everyday wear.

• Nano Mission
  • The Nano Mission, initiated by the Government of India in May 2007 with an allocation of Rs. 1000 crore for a span of 5 years, is overseen by the Department of Science and Technology (DST).
  • Acting as the successor to the Nano Science and Technology Initiative (NSTI) launched by DST in October 2001, the Nano Mission represents the second phase of India's endeavors in Nano Science and Technology.
  • Its primary focus areas encompass capacity-building in research, training, and the development of products and processes with applications in materials development, drug delivery, safe drinking water, among others.
  • Furthermore, it aims to foster collaborations between industry, research, and educational institutions, promoting public-private partnerships (PPPs), and encouraging foreign collaboration in nanotechnology programs.
• Indian Nanoelectronics Users Programme-Idea to Innovation (INUP-i2i)
  • This was launched by the Ministry of Electronics and Information Technology (MeitY), and is currently being executed at the Centre of Excellence in Nanoelectronics (CEN) at IISc, IIT Bombay, IIT Delhi, IIT Madras, IIT Kharagpur and IIT Guwahati.
  • This initiative has opened up significant avenues for the research and development (R&D) community across the nation by granting access to cutting-edge nanofabrication facilities.

• Following are the thrust areas identified by the Working Group of Nanotechnology:
  1. Post Moore Electronics beyond 10 nm
  2. Sensors (health, agriculture, security etc.)
  3. Organic Electronics
  4. Computational Nanoelectronics
  5. Setting up prototyping and incubation facilities for a range of devices/products
• In addition, the new thrust areas on a short term basis are as follows:
  • Development of the tools and equipment required for the fabrication and characterization of the nanotechnology.
  • UV LEDs
  • 2D materials beyond Graphene for nanoelectronics application"

• Health Risks:
  • Nanoparticles have been found to easily penetrate bodily tissues and can cause toxicity in organs like the liver and heart.
  • Certain nanomaterials, like titanium dioxide nanoparticles, have been linked to lung cancer in animal studies.
• Environmental Impact:
  • Carbon nanomaterials such as fullerenes and multi-walled nanotubes have been shown to affect crop yields and are toxic to aquatic life.
  • The use of nanopesticides and fertilizers can contribute to chemical pollution.
• Social and Legal Challenges:
  • Nanotechnology may exacerbate socioeconomic disparities by creating a "nano-divide" based on affordability.
  • Nanoparticles could potentially be exploited by terrorists to develop atomic weapons, posing risks to society.
  • Privacy concerns arise from the potential misuse of nanodevices for data collection without consent.
  • Automation through nanotech devices and machines may lead to job displacement as they can perform tasks more efficiently than humans.
• Ethical Considerations:
  • Exploitation of nanomaterials for commercial gain without considering negative consequences raises ethical concerns.
  • Incorporating nano-devices as human performance enhancers may raise ethical dilemmas.

The advancement of nanotechnology in India has been driven by the recognition of its vast potential to address critical societal challenges, including the provision of clean drinking water and healthcare services, while also fostering economic growth through the development of nanotech-based industries. Over the years, the government has made concerted efforts to support and promote nanotechnology initiatives in India, starting from the early 2000s. Looking ahead, continued investment in research, infrastructure, and skill development will be essential to harness the full potential of nanotechnology for the benefit of society and the economy in India.