Research Interest

Nanochemistry is the synthetic chemistry to make nanobuilding blocks. Now, nano become so infamous that, every sub-branch of Science and Technology prefer the prefix NANO- as we can see from the following diagram.











We demonstrate a simple solvothermal strategy to synthesize very stable monodispersed Co3O4 nanocrystals with spherical (0D) and hexagonal platelet (2D) morphologies depending on the control over reaction time. Our method is a direct synthesis method of Co3O4 via the production of b-Co(OH)2 as an intermediate. The sizes of as prepared Co3O4 nanospheres were found to be in 30-35 nm range and the hexagonal platelets are 3-4mm in diameter and ~100 nm in thickness. Further, the optical properties of the obtained Co3O4 particles were studied via a UV-visible spectrophotometer. Interestingly two distinct optical band gaps were observed for both morphologies of Co3O4 in their absorption spectra. Electrochemical performance of the synthesized materials was evaluated using Cyclic Voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge (GCD) in two electrode cell assembly (Co3O4/KOH/Co3O4). The results for the Co3O4 hexagonal platelet are only presented due to its highest capacitance than b-Co(OH)2, CoO and spherical Co3O4 nanoparticles. In the present work we have obtained ~476 F/g specific capacitance with very high energy and power density of 42.3 Wh kg-1 and 1.56 kW kg-1 respectively at a high current density of 0.5 Ag-1 without utilizing any large area support.

Text Box: Current research interest:
Nanotechnology, multifunctional materials, florescent semiconductors;
Hybrid nanocrystals for optical, electrical and biological applications;
Nanoparticles for energy & catalytic applications;

Metal alloy nanocrystal: these are one of the recent developments apart from the core@shell system. For instance, A@B or B@A, where both A & B are metal. We are developing few of these either in alloy and core@shell form. Applications, such as, catalysis, anti-bacterial activity, etc. have been being carried out on these nanocrystals.

Welcome to the NanoChemistry Laboratory

Department of Chemistry and NSNT, DU

This paper reports preparation of CeO2 nanocrystals by using oleic acid as a surfactant. A strong coordinating property of oleic acid toward (100) planes of the nanocrystals facilitated threedimensional (3D) assembly via oriented attachment of the nanocrystal building blocks to form (100) surface exposed porous cubic ceria by sharing {111} facets. As-synthesized materials were characterized by HRTEM, SEM, XRD, FTIR, Raman spectroscopy, and BET surface area analyzer. 3D morphology was established by STEM-HAADF technique and dark-field TEM. As-synthesized CeO2 nanocubes showed breakthrough in catalytic performance, enabling quantitative pX conversion and absolute selectivity in terephthalic acid (>99%). The presence of higher concentrations of oxygen vacancies (1.42 1021 cm3), owing to preferred exposed surfaces and lower individual crystallites size (6 nm), and larger surface area and pore size have been reasoned for high catalytic effectiveness. The catalyst recyclability experiments showed only 6% activity loss in TA yield in the fourth cycles.

A new synthesis strategy for fluorescent monodispersed 2-dimensional (2D) CdSe/CdS core/shell hexagonal platelet nanocrystals has been demonstrated. Due to the stronger affinity of -NH2 group of oleylamine to the (0001Se) facet comprising three dangling bonds in CdSe seeds, oleylamine acts as the sole responsible surfactant to hinder the growth of CdS shell in 0001 and 0001- facets and helps the shell growth anisotropically in <100> direction. The as-synthesized products were thoroughly characterized using XRD, TEM/HRTEM, HAADF and STEM techniques for the knowledge of crystal structure, growth mechanism and the position of seed inside a core/shell nanocrystal. Optical absorption, PL, PLE and TRPL studies revealed efficient photoexcitation and possibility of polarized emission from the 2D core/shell nanocrystals.

Laboratory resources: Glove Box, Fume hood, PID controlled ovens, Schlenk line, hydrothermal/solvothermal apparatus, sonochemical synthesis apparatus, basic chemical synthesis facilities, minor equipments, etc.

Characterization facilities: Collaboration with M.Tech nano (NSNT) and USIC, DU : XRD, HRTEM, UV-Vis, PL, SEM, VSM, Raman, particle size analyzer, LB, etc.


We report novel bimetallic Ag@AgxNiy core@graded-alloy-shell nanoparticles (CGAS NPs), i.e. single Ag core NPs shelled by an AgxNiy graded alloy and stabilized by the CTAB surfactant employing a novel synthesis method. These Ag@AgxNiy CGAS NPs demonstrated superior catalytic performance in the synthesis of biologically active 3-amino alkylated indoles under green conditions.