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Materials Letters, 2004
A simple gel to crystal conversion route has been followed for the preparation of TiO 2 at 80 -10... more A simple gel to crystal conversion route has been followed for the preparation of TiO 2 at 80 -100 jC under refluxing conditions. Freshly prepared titanium hydroxide gel is allowed to crystallize under refluxing and stirring conditions for 6 -12 h. Formation of nanocrystallites of anatase is confirmed by X-ray diffraction (XRD) study. The anatase phase converts into rutile when calcined at 700 jC for 12 h. Raman scattering experiments were also performed to confirm both anatase and rutile phases. Transmission electron microscope (TEM) investigations revealed that the average particle size is 10 nm for the anatase phase whereas it is 35 nm for the rutile polymorph. D
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2004
When tin oxide is doped with Sb 2 O 3 and CoO, it shows highly nonlinear current (I)-voltage (V) ... more When tin oxide is doped with Sb 2 O 3 and CoO, it shows highly nonlinear current (I)-voltage (V) characteristics. Addition of CoO leads to creation of oxygen vacancies and helps in sintering of SnO 2 . Antimony oxide acts as a donor and increases the conductivity. The results are nearly same when antimony oxide is replaced by tantalum oxide. The grain size of these sintered ceramics varies from 5 to 7 m and the grain boundary barrier height (Φ B ) is in the range of 0.5 eV. The observed nonlinear coefficient (α) is 25 and 27 for antimony and tantalum oxide, respectively and the breakdown field is in the range of 1250 V cm −1 .
Materials Letters, 2004
A simple gel to crystal conversion route has been followed for the preparation of TiO 2 at 80 -10... more A simple gel to crystal conversion route has been followed for the preparation of TiO 2 at 80 -100 jC under refluxing conditions. Freshly prepared titanium hydroxide gel is allowed to crystallize under refluxing and stirring conditions for 6 -12 h. Formation of nanocrystallites of anatase is confirmed by X-ray diffraction (XRD) study. The anatase phase converts into rutile when calcined at 700 jC for 12 h. Raman scattering experiments were also performed to confirm both anatase and rutile phases. Transmission electron microscope (TEM) investigations revealed that the average particle size is 10 nm for the anatase phase whereas it is 35 nm for the rutile polymorph. D
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2004
When tin oxide is doped with Sb 2 O 3 and CoO, it shows highly nonlinear current (I)-voltage (V) ... more When tin oxide is doped with Sb 2 O 3 and CoO, it shows highly nonlinear current (I)-voltage (V) characteristics. Addition of CoO leads to creation of oxygen vacancies and helps in sintering of SnO 2 . Antimony oxide acts as a donor and increases the conductivity. The results are nearly same when antimony oxide is replaced by tantalum oxide. The grain size of these sintered ceramics varies from 5 to 7 m and the grain boundary barrier height (Φ B ) is in the range of 0.5 eV. The observed nonlinear coefficient (α) is 25 and 27 for antimony and tantalum oxide, respectively and the breakdown field is in the range of 1250 V cm −1 .