ECE Seminar - Liquid Crystals and Nanoscience : Fundamental aspects for Energy and Targetted Sensing Applications
Liquid crystalline materials are delicate in nature existing between the crystalline solids and isotropic liquids. Owing to their semiconducting nature, disc-like LCs have proven themselves as a potential materials for modern optoelectronic applications due to their self-assembling and quasi-one-dimensional charge transport characteristics. The disc-like LCs exhibit ambipolar charge transport with charge career mobility of the order of 0.1 - 1 x 10-3 cm2/Vs [1-3]; however, the mobility in devices remarkably depends on the molecular ordering and material’s stability. This feature is significantly important for the organic electronic applications.
Due to high charge carrier mobility, these materials can also be used as hole-transporting material in solar cells and organic light-emitting diodes. The 1D charge transport restricts the carrier recombination at the interfaces resulting in a better device performance [4].
In the last part, we have synthesized an easy transformation of chestnut-derived biowaste into reduced graphene oxide (rGO) and pyridinic-N-dominated nitrogen-doped rGO (NCS-rGO). The synthesized catalyst exhibits better ORR activity with an onset and half-wave potential of 0.93 V and 0.86 V, respectively, along with a high diffusion-limiting current density of 5.05 mA cm-2. Under alkaline conditions, we found that NCS-rGO shows an unusually high electrocatalytic activity that is superior to that of the commercial 20% Pt/C catalyst [5]. With the same biowaste, we have also prepared C-dots which has been used for selective detection of arsenic.
In this presentation, the following three topics will be covered:
- Charge transport in semiconducting LCs and its use in organic electronics
- Discotic LCs as hole-transporting materials for solar cell applications
- Biowaste derived nanostructure for energy applications and selective detection
References:
- M. Gupta et al., Chem. Comm. 2023, https://doi.org/10.1039/D3CC02440G
- P. Mahesh et al., Journal of Materials Chemistry C, 8, 9252, 2020.
- A. Shah et al., New Journal of Chemistry, 44, 14872, 2020.
- D. Singh et al., Liquid Crystals, 2023, https://doi.org/10.1080/02678292.2023.2188616
- A. Shah et al., New Journal of Chemistry, 47, 1360, 2023.
Dr. Dharmendra Pratap Singh holds the position of an Associate Professor at Université du Littoral Côte d'Opale (ULCO), France. He is a member of the Unité de Dynamique et Structure des Matériaux Moléculaires (UDSMM) laboratory and head of the first-year cycle of Industrial Engineering at the Engineering School of the ULCO. Dr. Singh obtained his M.Sc. and Ph.D. degrees from the Department of Physics, the University of Lucknow, India in 2008 and 2016, respectively. He completed his Ph.D. on Liquid crystal-Nanocomposites. His current research activities are focused on the discotic, ferroelectric, nematics and ferroelectric nematic liquid crystals along with their nanocomposites for studying the charge transport mechanisms and their applications for energy, sensing, thermoelectric, optoelectronics, photovoltaics and organic electronics. Presently, he is acting as an Associate Editor of the Frontiers in Coatings, Dyes and Interface Engineering (Frontiers) and Guest lead editor of the Advanced Science and Technology of Defects in Soft Matter (MDPI). He is the recipient of the Young Scientist Award by the Indian Science Congress in 2017 for physical sciences. He is the recipient of the best research award by the Indian Liquid Crystal Society in 2012. He is also the recipient of an early career award at Cambridge University in 2013, the Best research award by the Korean display society in 2015 and the Raman-Charpak Fellowship which is a doctoral student exchange fellowship between India and France. He has published around 90 research articles and 5 book chapters in international journals like Physical Reviews, Journal of applied physics, Journal of Materials Chemistry C, Journal of Physical Chemistry B, and Journal of Physics D: Applied Physics, etc. He has supervised 3 Ph.D. theses and principal investigator of PHC Star, Procore, Galilée, Alliance and Samuel de Champlain projects with South Korea, Hong Kong, Italy, the United Kingdom and Canada, respectively. Presently, he is also serving as a reviewer for 25 journals from RSC, ACS, AIP, Elsevier, Springer, APS, etc.