MINERAS BUENAVENTURA 0.95% 2.84%

Following the thermogravimetric measurements, various annealin

500 °C were investigated. The XRD patterns of the samples after annealing are reported in figure 6.4 (a,b).

XRD pattern of anatase nanotubes annealed at different temperature enhanced picture of the main peak.

The purpose of this analysis was to establish the most suitable temperature, which allows the complete formation of the anatase structure fro

collapse of the nano

a that the intensity of the peaks, crystallinity of the samples increased with inc

optimal annealing temperature

Following the thermogravimetric measurements, various annealin

500 °C were investigated. The XRD patterns of the samples after

XRD pattern of anatase nanotubes annealed at different temperature enhanced picture of the main peak.

The purpose of this analysis was to establish the most suitable temperature, which allows the complete formation of the anatase structure fro

collapse of the nano-morphology and the formation of

a that the intensity of the peaks, with increasing

optimal annealing temperature

Following the thermogravimetric measurements, various annealin

500 °C were investigated. The XRD patterns of the samples after

XRD pattern of anatase nanotubes annealed at different temperature enhanced picture of the main peak.

The purpose of this analysis was to establish the most suitable temperature, which allows the complete formation of the anatase structure from the titanate precursor, morphology and the formation of

a that the intensity of the peaks, reasing annealing

Following the thermogravimetric measurements, various annealing temperatures in 500 °C were investigated. The XRD patterns of the samples after

XRD pattern of anatase nanotubes annealed at different temperatures and (b) an

The purpose of this analysis was to establish the most suitable temperature, which m the titanate precursor, morphology and the formation of

and therefore, the annealing temperature

g temperatures in 500 °C were investigated. The XRD patterns of the samples after

s and (b) an

The purpose of this analysis was to establish the most suitable temperature, which m the titanate precursor, morphology and the formation of

therefore, the temperature. This

shows that above 400 values of the

crystalline. Therefore,

and 400 °C. In this temperature range the intensity of the domi

2θ = 25.2° still suggests a nanostructure.

TEM images were then taken for the samples calcinated at different temperatures. These are shown in figure 6.

observed for the samples calcin 400 °C the sample has already

of the nanotubular structure and formation of bulkier material. Furthermore, the sample treated at 500

particulates

Figure 6.5 TEM images of anat

shows that above 400 of the same peak crystalline. Therefore,

and 400 °C. In this temperature range the intensity of the domi 25.2° still suggests a nanostructure.

TEM images were then taken for the samples calcinated at different temperatures. These are shown in figure 6.

bserved for the samples calcin the sample has already

of the nanotubular structure and formation of bulkier material. Furthermore, the sample treated at 500

particulates of anatase

Figure 6.5 TEM images of anat Chapter 6. Synthe

shows that above 400 °C the intensity peak are decreasing,

crystalline. Therefore, the ideal annealing temperature appears to range between 350 and 400 °C. In this temperature range the intensity of the domi

25.2° still suggests a nanostructure.

TEM images were then taken for the samples calcinated at different temperatures. These are shown in figure 6.5.

bserved for the samples calcined

the sample has already started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the sample treated at 500 °C clearly shows

of anatase.

Figure 6.5 TEM images of anat

Chapter 6. Synthesis and Characterisation of TiO

intensity of the main peak are decreasing, suggesting

the ideal annealing temperature appears to range between 350 and 400 °C. In this temperature range the intensity of the domi

25.2° still suggests a nanostructure.

TEM images were then taken for the samples calcinated at different temperatures. The homogeneous nanotubular morphology can be ed at 300 and 350

started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the

°C clearly shows loss of nanotubes and presence of

Figure 6.5 TEM images of anatase nanotubes annealed at different temperatures. is and Characterisation of TiO

of the main peak suggesting the

the ideal annealing temperature appears to range between 350 and 400 °C. In this temperature range the intensity of the domi

TEM images were then taken for the samples calcinated at different temperatures. homogeneous nanotubular morphology can be at 300 and 350 °C. However, it can be seen that started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the

loss of nanotubes and presence of

se nanotubes annealed at different temperatures. is and Characterisation of TiO

of the main peak is increasing

the structure is becoming the ideal annealing temperature appears to range between 350 and 400 °C. In this temperature range the intensity of the dominant anatase peak at

TEM images were then taken for the samples calcinated at different temperatures. homogeneous nanotubular morphology can be

°C. However, it can be seen that started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the

loss of nanotubes and presence of

se nanotubes annealed at different temperatures. is and Characterisation of TiO2Anatase nanotubes

s increasing and the structure is becoming the ideal annealing temperature appears to range between 350

nant anatase peak at

TEM images were then taken for the samples calcinated at different temperatures. homogeneous nanotubular morphology can be

°C. However, it can be seen that started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the loss of nanotubes and presence of larger size

se nanotubes annealed at different temperatures. Anatase nanotubes

FWHM structure is becoming more the ideal annealing temperature appears to range between 350 nant anatase peak at

TEM images were then taken for the samples calcinated at different temperatures. homogeneous nanotubular morphology can be °C. However, it can be seen that at started to lose its morphology suggesting the collapse of the nanotubular structure and formation of bulkier material. Furthermore, the larger size

It can therefore be concluded that the optimal annealing temperature should be between 350 and 400

reported in paragraph 6.2.

6.3.2 Investigation of the optimal heating rate

In order to optimi figure 6.6

peak (2θ =

This analysis suggests that a high heating rate favours the formation of larger crystal in the sample and therefore a slower heating rate is required to prevent

in the sample.

It can therefore be concluded that the optimal annealing temperature should be between 350 and 400

reported in paragraph 6.2.