National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Nanoparticle. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

Band alignment and charge transfer pathway in three phase anatase-rutile-brookite TiO2 nanotubes: An efficient photocatalyst for water splitting

Abstract: The study reports electrochemical synthesis, phase evolution and hydrogen generation efficiency of anatase, anatase-rutile and anatase-rutile-brookite (ARB) TiO 2 nanotubes for the first time. The SEM and TEM micrographs confirm the tubular morphology of the samples. The presence of anatase, rutile and brookite phases in a single nanotube is confirmed from high resolution TEM analysis. The water splitting efficiency of the three systems are studied under one sun illumination. It is observed that the anatase-rutile-brookite TiO 2 nanotubes are highly efficient compared to anatase-rutile or anatase TiO 2 nanotubes. The hydrogen generated by ARB composites, after four hours of one sun illumination, is found to be nearly twice that of anatase TiO 2 nanotubes and 1.6 times that of anatase-rutile TiO 2 nanotubes. The results suggest that the ARB in single nanotube having two junction interfaces, highly facilitate inter-particle charge transfer compared to single junction anatase-rutile or bare anatase TiO 2 nanotubes. From the deconvolution of PL spectra and the synchrotron radiation assisted valence band edge analysis, the band diagram for the anatase-rutile-brookite phase is constructed. The charge separation and its transfer pathway for efficient photo-assisted water splitting are delineated. This opens a new route for the simple synthesis and study of tri-phase TiO 2 for efficient photocatalytic water splitting compared to the widely studied two phase TiO 2 .

Microwave-assisted MgO NP catalyzed one-pot multicomponent synthesis of polysubstituted steroidal pyridines

Abstract: The present study reports a highly efficient and green synthetic route for the synthesis of steroidal pyridines. The synthetic methodology involves a microwave-assisted one-pot multicomponent reaction using MgO NPs as a heterogeneous, mild and reusable catalyst. The synthesized MgO NPs were characterized by FTIR, TGA/DTA and XRD analyses. The remarkable features of this protocol include simple operational procedure, shorter reaction profiles, mild reaction conditions, minimal chemical waste and economic viability. The recyclability of the catalyst and high yield of products make the proposed method a sustainable alternative.

Cracking of Cellulose over Supported Metal Catalysts

Abstract: Cellulose is cracked over supported Pt or Ru catalysts under hydrogenolysis conditions in water to give sorbitol as a main product. Among the catalysts tested, Pt/γ-Al2O3 gave the highest yield and selectivity, and this catalyst was recyclable in repeated runs. It is proposed that cellulose is hydrolyzed by in situ generated acid sites to form glucose, and glucose is immediately reduced to sorbitol over the metal catalyst.