Publications by authors named "Jayaramakrishnan Velusamy"

Challenging the basis of our chemical intuition, recent experimental evidence reveals the presence of a new type of intrinsic fluorescence in biomolecules that exists even in the absence of aromatic or electronically conjugated chemical compounds. The origin of this phenomenon has remained elusive so far. In the present study, we identify a mechanism underlying this new type of fluorescence in different biological aggregates.

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The toxic nature of inorganic nanostructured materials as photocatalysts is often not accounted for in traditional wastewater treatment reactions. Particularly, some inorganic nanomaterials employed as photocatalysts may release secondary pollutants in the form of ionic species that leach out due to photocorrosion. In this context, this work is a proof-of-concept study for exploring the environmental toxicity effect of extremely small-sized nanoparticles (<10 nm) like quantum dots (QDs) that are employed as photocatalysts, and in this study, cadmium sulfide (CdS) QDs are chosen.

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Perovskite solar cells (PSCs) are an evolving photovoltaic field with the potential to disrupt the established silicon solar cell market. However, the presence of many transport barriers and defect trap states at the interfaces and grain boundaries has negative effects on PSCs; it decreases their efficiency and stability. The purpose of this work was to investigate the effects on efficiency and stability achieved by quaternary theophylline additives in MAPbI PSCs with the structure FTO/TiO/perovskite/spiro-OMeTAD/Ag.

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Plasmonic nanocrystals (NCs) assisted phase transition of two-dimensional molybdenum disulfide (2D-MoS) unlashes numerous opportunities in the fields of energy harvesting via electrocatalysis and photoelectrocatalysis by enhancing electronic conductivity, increasing catalytic active sites, lowering Gibbs free energy for hydrogen adsorption and desorption, etc. Here, we report the synthesis of faceted gold pentagonal bi-pyramidal (Au-PBP) nanocrystals (NC) for efficient plasmon-induced phase transition (from 2 H to 1 T phase) in chemical vapor deposited 2D-MoS. The as-developed Au-PBP NC with the increased number of corners and edges showed an enhanced multi-modal plasmonic effect under light irradiations.

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We present a simple but robust strategy to engineering heteroatoms (N, S) on carbon dots (CDs) surface that results in a collection of enhanced photoluminescence (PL) emissions. The use of citric acid (CA) and 2-Imidazolidinethione (2-IZT) as precursors was envisioned to study the impact of thermolysis process on the PL properties. The proposed strategy, implemented at two different temperatures (180 °C and 200 °C), is suitable to produce CDs with tunable PL and quantum yield (QY) up to ∼32%.

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