"I have about ten years of research experience in photovoltaics, nanoscience, optics, and plasmonics. I was part of various individual and group research projects in prestigious institutes like IIT Delhi, IISc Bangalore, IISER Pune, and NIT Calicut. Currently, I am part of PSG Institute of Advanced Studies, Coimbatore. My research findings have been reported in peer-reviewed international journals and prestigious conferences. The highlights of major research projects are discussed here."
Photocurrent Enhancement in Organic Solar Cells using Au-WS2 Nanohybrids
The synergistic plasmonic effects of multi-shaped Au nanostructures hybridized with few-layer WS2 nanosheets were utilized to improve the organic solar cells' photocurrent. An efficiency enhancement of more than 15% and an external quantum efficiency improvement in a broad wavelength range of 350-700 nm were demonstrated by incorporating these Au-WS2 nanohybrids as an interlayer between hole-transport and photoactive layers. The efficiency enhancement is mainly due to the improved photocurrent via broad-range plasmonic effects of Au nanostructures.
Plasmonic organic solar cells were fabricated by incorporating Ag nanostructures simultaneously in cathode buffer layer and active layer. The devices exhibited performance enhancement in a broad wavelength range leading to an efficiency enhancement of more than 15%. The higher efficiency is due to the simultaneous rise in both the exciton generation and dissociation rates caused by the combined plasmonic effects of multi-positional Ag nanostructures.
Plasmonic Organic Solar Cells Based on Multi-positional Ag Nanostructures
Optical Absorption Enhancement in Multi-positional Ag Nanostructure Incorporated Organic Solar Cells
High absorption enhancement in a broad spectral range is highly desirable to boost the efficiency of organic solar cells. The active layer absorption enhancement in a broad wavelength range was obtained by simultaneously incorporating Ag nanostructures in dual locations. An enhancement factor of 1.66 was achieved by optimizing the size and period of Ag nanospheres.
Influence of Ag Nanostructure Shape and Location on Organic Solar Cell Active Layer Absorption
The influence of Ag nanostructure location on the optical absorption of the active layer was numerically investigated using finite-difference time-domain (FDTD) simulations. The absorption enhancement was found to be sensitive to the shape and location of the nanostructures. The highest enhancement factors of 1.53 and 1.61 were obtained for Ag nanospheres and nanocubes, respectively, at top location. The larger absorption enhancement obtained at the top location is attributed to the formation of hotspot due to the plasmon coupling of adjacent nanostructures.
Organic Bistable Memory Devices Based on Molybdnum Trioxide Nanostructures
Organic bistable memory devices were fabricated by embedding a thin layer of molybdenum trioxide between two tris-(8-hydroxyquinoline)aluminum layers. The device exhibited excellent switching characteristics with a high ON/OFF current ratio of more than a thousand. The device showed repeatable write–erase capability and good stability in both the ON and OFF states.