2D material synthesis is one of the main challenges to achieving their industrial application. The three main drivers of 2D layered material synthesis are firstly, to achieve scalable synthesis of 2D layers with large domain sizes for high electron mobility devices useful for electronics and non-planar 2D materials for bulk applications (e.g., batteries, catalysis, composites). Secondly, to control the heterogeneity in the crystal for understanding the point defects, doping, and grain boundaries for improving the crystallinity and studying the material properties. Thirdly, to control the number of layers and their orientation/stacking. 

I have used techniques like pulsed laser deposition, and chemical vapor deposition for depositing different 2D materials like MoS2, WS2, SnS, and MoO3. 

Currently, I am working on Plasma Enhanced Chemical vapor deposition (PECVD) to study low-temperature growth of 2D materials for back-end-of-the-line integration.

Although, Humans can distinguish 1 trillion olfactory stimuli making human nose a remarkable gas sensor. But it fails to distinguish all the available odors and sometimes its not safe to do so. Other than humans dogs have been extensively used for sniffing. Unfortunately the need of modern civilization cannot be met by both humans and dogs. Gas sensing is one of the most important field required for environmental monitoring, safety, security, energy saving, health, foods etc.  

PLD comprises of a focused high-energy pulsed laser beam which ablates the material from the desired target, resulting in a high energy plume of target atoms which upon incident can migrate freely on the substrate, which results in high uniformity and large growth area. The use of a pulsed laser beam with the flexibility to control the laser wavelength and fluence enables a precise control over the growth rate this helps in controlling the layer number and thickness of the film. 

2D materials have a vast verity but due to the use of high-energy laser in PLD, it can ablate almost all materials with congruent transfer of target composition. Hence, maintaining the stoichiometry of the material in the film and opening the opportunity verity of 2D TMDC layers and 2D alloys. 

Nanoparticle are used in verity of application ranging from catalysis, Surface plasmon resonance, sensors. Recently, metal nanoparticles have received special attention for biological application like toxicity evaluation, therapeutic evaluation, radiosensitizer application, antimicrobial properties, photothermal properties.

Integrated gas phase synthesis (IGPS) setup is an In-house developed setup to obtain size-selected metal nanoparticle, alloy nanoparticles and core shell nanoparticles. It consists of a spark generator to produce metal nanoparticles with a spark discharge between the electrode of metals. The evaporated material cools down rapidly by expansion and on mixing with the carrier gas resulting in the formation of small-sized primary cluster by the homogeneous nucleation process. Inside impactor aerosol is diluted by mixing the extra carrier gas, the particles are charged positively and negatively using Kr-85 neutralizer. Aerosol is further diluted with sheath flow as it enters differential mobility analyzer (DMA), here particles are sorted by their differential mobility due to an applied electric field. Agglomerates of metal particles then enters the sintering furnace where they get compacted to form spherical nanoparticles. Inside ESP the particles gets deposited under an applied potential directly onto the substrate.

 IGPS is a unique technique to obtain impurity free size-selected nanoparticles for the fundamental studies and application in gas sensing, photoelectrochemical water splitting and thermoelectric energy harvesting.