Sol-Gel Synthesis of TiO2 Nanosheets

Philip
Whong

Rutgers
University

Department
of Chemical and Biochemical Engineering

Research
Abstract: Sol-Gel Synthesis of TiO_­2 ­Nanosheets

In the last decades, the research progress on the
design and development of TiO₂ based materials has been instrumental, especially
due to the
r reinforced
interest in semiconductor materials for photovoltaics, photocatalysis, and
electrochemistry. More specifically, crystalline rutile or anatase are very
promising supports for both metal and metal oxide catalysts. Contrary to rutile, anatase
polymorph of TiO₂’s
crystalline structure, exhibits higher specific surface area.  However, the main challenge
in the field of synthesis of high surface area TiO₂ is its tendency to
aggregate even at relatively mild temperatures.

To improve the functionality of TiO₂
nanoparticles, a variety of emerging synthesis methods attempt to enhance TiO₂
nanoparticle surface area and structure. 
For example, TiO₂
has been synthesized through, colloidal synthesis, microemulsion method, and
pyrolysis.  In our approach, TiO₂
nanoparticles have been synthesized from Titanium Isopropoxide
precursor via a modified sol- gel route.  Sol-gel synthesis
is an attractive method of preparing nanomaterial TiO₂
as it uses low temperatures for reaction synthesis.  Non-toxic biomass templates were incorporated
in our sol- gel method with varying synthesis
temperatures for preparation of TiO₂
nanoparticles. Results showing that TiO₂
nanoparticles with improved surface area were produced.  Samples showed improve surface area with BET values
greater than 150 m²/g.  SEM results revealed unique morphology of TiO₂
nanosheets incorporated into a porous network.  In addition, characterization techniques such
as Raman and XRD were performed on the TiO₂
samples, revealing the formation of anatase structure. New Raman
features were found that
could probably ascribed either to TiO₂
particles with crystallite size less than 20nm or small oxyhydroxide domains. Further
studies will explore varying concentrations of precursors, calcination
temperatures, and reaction times for optimal synthesis parameters for higher
surface area.