Biswanath Dutta

Mesoporous Manganese Oxide Catalyzed Aerobic Oxidative Coupling of Anilines To Aromatic Azo Compounds.

Herein we introduce an environmentally friendly approach to the synthesis of symmetrical and asymmetrical aromatic azo compounds by using air as the sole oxidant under mild reaction conditions in the presence of cost-effective and reusable mesoporous manganese oxide materials.

Mesoporous Iron Sulfide for Highly Efficient Electrocatalytic Hydrogen Evolution

We report a facile synthetic protocol to prepare mesoporous FeS2 without the aid of hard template as an electrocatalyst for the hydrogen evolution reaction (HER). The mesoporous FeS2 materials with high surface area were successfully prepared by a sol-gel method following a sulfurization treatment in an H2S atmosphere. A remarkable HER catalytic performance was achieved with a low overpotential of 96 mV at a current density of 10 mA·cm-2 and a Tafel slope of 78 mV per decade under alkaline conditions (pH 13). The theoretical calculations indicate that the excellent catalytic activity of mesoporous FeS2 is attributed to the exposed (210) facets. The mesoporous FeS2 material might be a promising alternative to the Pt-based electrocatalysts for water splitting.

Cross dehydrogenative coupling of N-aryltetrahydroisoquinolines (sp3 C–H) with indoles (sp2 C–H) using a heterogeneous mesoporous manganese oxide catalyst

We disclose a novel, heterogeneous catalytic approach for selective coupling of C1 of N-aryltetrahydroisoquinolines with C3 of indoles in the presence of mesoporous manganese oxides. Our work involves a detailed mechanistic investigation of the reaction on the catalyst surface, backed by DFT computational studies, to understand the superior catalytic activity of manganese oxides.

Mesoporous cobalt/manganese oxide: a highly selective bifunctional catalyst for amine–imine transformations

Herein, we discuss a heterogeneous catalytic protocol using cobalt doped mesoporous manganese oxide for amine–alcohol cross-coupling to selectively produce symmetric or asymmetric imines. Thorough investigations on the surface chemistry and physical properties of the material revealed its outstanding oxidation–reduction properties and reaction mechanism which was supported by quantum mechanical calculations done by using density functional theory (DFT).

Enhanced Catalytic Properties of Molybdenum Promoted Mesoporous Cobalt Oxide: Structure-Surface-Dependent Activity for Selective Synthesis of 2-Substituted Benzimidazoles

High‐valent molybdenum ions were substituted into the cobalt oxide lattice through a one step, sol‐gel method and investigated for selective synthesis of 2‐substituted benzimidazoles. Catalyst synthesis involves surfactant assisted soft templating inverse micelle method, which forms mesopores by interconnected intraparticle voids. Substitutional doping of Mo6+ resulted in materials with modified structural, morphological, surface, and redox properties. The catalytic activity increased with Mo concentration until an optimum amount (3 % Mo incorporation). Modified material shows lattice expansion, increased surface oxygen vacancies, and high surface area, which are responsible for the higher catalytic activity in selective benzimidazole synthesis reaction. A strong correlation between surface properties of the catalyst and the product selectivity was observed and plausible mechanistic and kinetic data are proposed and collected, respectively.

Cross Sectional Analysis of Cation Doped Transition Metal Oxide Mesoporous Catalyst Materials

UCT (University of Connecticut) mesoporous transition metal oxide materials are synthesized using an inverse micelle soft template and unique NOx chemistry. The resulting aggregated nanoparticles exhibit tunable pore structures, excellent thermal stability, and easily accessible oxidation states which contribute to a wide range of organic catalytic transformations [1]. Among the variety of transition metal oxide systems, mesoporous manganese oxides have proven to be efficient catalysts in the oxidation of alcohols to carboxylic acids. In addition to organic catalysis, there is interest in using the various mesoporous metal oxides in other fields such as energy and advanced separations.