Chapter 1. Introduction.- Part 1: Synthesis and characterizations.- Chapter 2. Synthesis of carbon allotropes in nanoscale regime.- Chapter 3. Scanning tunneling microscopy (STM) imaging of carbon nanotropes: C60, CNT and Graphene.- Chapter 4. Carbon: A phantom for nanocomposite driven applications.- Chapter 5. Carbon-Based Nanocomposites: Processing, Electronic Properties And Applications.- Chapter 6. Tuning of SPR and Structural Properties of Cu-fullerene metal nanocomposites.- Part 2: Theoretical and computational study.- Chapter 7. Theoretical and Computational Investigations of Carbon Nanostructures.- Chapter 8. Edge State Induced Spintronic Properties of Graphene Nanoribbons: A Theoretical Perspective.- Chapter 9. Carbon Nanotube Field Effect Transistors (CNFETs): Structure, Fabrication, Modeling and Performance.- Chapter 10. Carbon Nanomaterials for Emerging Electronic Devices and Sensors.- Part 3: Devices and applications.- Chapter 11. Applications of Carbon based nanomaterials in Health and Environment: Biosensors, Medicine and Water treatment.- Chapter 12. Large Area Graphene and Their Use as Flexible Touchscreens.- Chapter 13. Carbon Nanotube Alignment Techniques and their Sensing Applications.- Chapter 14. Reduced Graphene Oxide Photodetector Devices for Infra-Red Sensing.- Chapter 15. Characteristic response transition of reduced graphene oxide as hydrogen gas sensor- the effect of temperature and doping concentration.- Chapter 16. Carbon-Based Electrodes for Perovskite Photovoltaics.- Chapter 17. Emerging Carbon Nanomaterials for Organic and Perovskite based Optoelectronics Device Applications.