Publications by authors named "Gurudayal"

Dysregulation in Janus kinase-Signal Transducer and Activation of Transcription (JAK-STAT) pathway is closely linked to various cancer types. The N-terminal domain (NTD) of STAT proteins, upon dimerization, assumes a multifaceted role with remarkable adaptability in mediating interactions between proteins. Consequently, the strategic targeting of the N-terminal domain of STATs has emerged as a promising tactic for disrupting dimerization and impeding the translocation of STAT proteins.

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An expeditious method for the synthesis of homo and heterochiral dipeptides containing l-alanine and d/l 2-methyl allo-hydroxyl prolines was developed using direct aminolysis of bicyclic lactones derived from d/l alanine. The impact of C-2 methylation and its spatial orientation on the pyrrolidine ring puckering and prolyl amide bond configuration was ascertained by solution NMR studies. The present studies reveal that C-2 methylation causes the prolyl amide bond to exist exclusively in the trans geometry in both homo- and heterochiral dipeptides.

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Photoelectrochemical (PEC) water oxidation is considered to be the rate-limiting step of the two half-reactions in light-driven water splitting. Consequently, considerable effort has focused on improving the performance of photoanodes for water oxidation. While these efforts have met with some success, the mechanisms responsible for improvements resulting from photoanode modifications are often difficult to determine.

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Photoelectrochemical (PEC) cells are attractive for storing solar energy in chemical bonds through cleaving of water into oxygen and hydrogen. Although hematite (α-Fe O ) is a promising photoanode material owing to its chemical stability, suitable band gap, low cost, and environmental friendliness, its performance is limited by short carrier lifetimes, poor conductivity, and sluggish kinetics leading to low (solar-to-hydrogen) STH efficiency. Herein, we combine solution-based hydrothermal growth and a post-growth surface exposure through atomic layer deposition (ALD) to show a dramatic enhancement of the efficiency for water photolysis.

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Photoelectrochemical water splitting half reactions on semiconducting photoelectrodes have received much attention but efficient overall water splitting driven by a single photoelectrode has remained elusive due to stringent electronic and thermodynamic property requirements. Utilizing a tandem configuration wherein the total photovoltage is generated by complementary optical absorption across different semiconducting electrodes is a possible pathway to unassisted overall light-induced water splitting. Because of the low photovoltages generated by conventional photovoltaic materials (e.

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We report a simple method to produce a stable and repeatable photoanode for water splitting with a core-shell hematite (α-Fe2O3) nanorods system by combining spray pyrolysis and hydrothermal synthesis. Impedance spectroscopy revealed passivation of the surface states by the shell layer, which results in an increase of the charge injection through the hematite conduction band. In pristine hematite more holes are accumulated on the surface and the charge transfer to the electrolyte occurs through surface states, whereas in the core-shell hematite photoanode the majority of hole transfer process occurs through the valence band.

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We report the synthesis of iron based titanate (Fe2TiO5) thin films using a simple low cost hydrothermal technique. We show that this Fe2TiO5 works well as a photoanode for the photoelectrochemical splitting of water due to favorable band energetic. Further characterization of thin films including band positions with respect to water redox levels has been investigated.

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Here, we report a significant improvement of the photoelectrochemical (PEC) properties of hematite (α-Fe2O3) to oxidize water by doping with manganese. Hematite nanorods were grown on a fluorine-treated tin oxide (FTO) substrate by a hydrothermal method in the presence on Mn. Systematic physical analyses were performed to investigate the presence of Mn in the samples.

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In natural photosynthesis, the water splitting reaction of photosystem II is the source of the electrons/reducing equivalents for the reduction of carbon dioxide to carbohydrate while oxygen is formed as the by-product. Similarly, for artificial photosynthesis where the end product is a solar fuel such as hydrogen, a water splitting-oxygen evolving system is required to supply high energy electrons to drive the reductive reactions. Very attractive candidates for this purpose are iron based semiconductors which have band gaps corresponding to visible light and valence band energies sufficient to oxidise water.

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