Electrode surface modification using iron(II) phthalocyanine immobilized via electrografting and click chemistry and clicked onto azide-functionalized quantum dots: applications in electrocatalysis
- Authors: Nxele, Siphesihle Robin
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3464 , vital:20501
- Description: Tetrakis(5-hexynoxy)Fe(II) phthalocyanine was used alone and in combination with quantum dots (QDs) in order to test the electrocatalytic ability with hydrazine and paraquat as the analytes of interest. This novel phthalocaynine was successfully synthesised and characterized using various characterisation techniques. The QDs used were the well-known core-shell CdSe/ZnS nanostructures. The fabrication of glassy carbon electrodes involved covalent attachment by electrochemical grafting and click chemistry for the first part of the work and the second part involved the conjugation of the synthesised QDs and the phthalocyanine by click chemistry. This approach of conjugating these nanostructures introduced another aspect of novelty to the work reported in this thesis. The immobilisation of this conjugate on a glassy carbon electrode (GCE) was achieved by adsorption. Characterisation techniques such as infrared spectroscopy, x-ray diffractometry, UV/vis spectroscopy, transmission electron microscopy and x-ray photoelectron spectroscopy were used to characterise the molecules and conjugates of interest. With respect to the electrocatalytic part of the work, electrode surface characterisation involved scanning electrochemical microscopy and cyclic voltammetry to determine changes in the nature of the surface as well as reactivity of the surface at different modification steps. Detection limits and the sensitivity determined for the electrocatalysts fabricated here proved to be an improvement compared to other reported work involving phthalocyanines and the test analytes chosen for application. With respect to the conjugate, the electrocatalytic ability was improved when the QDs and phthalocyanine were combined using click chemistry compared to using the phthalocyanine alone.
- Full Text:
- Date Issued: 2016
- Authors: Nxele, Siphesihle Robin
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3464 , vital:20501
- Description: Tetrakis(5-hexynoxy)Fe(II) phthalocyanine was used alone and in combination with quantum dots (QDs) in order to test the electrocatalytic ability with hydrazine and paraquat as the analytes of interest. This novel phthalocaynine was successfully synthesised and characterized using various characterisation techniques. The QDs used were the well-known core-shell CdSe/ZnS nanostructures. The fabrication of glassy carbon electrodes involved covalent attachment by electrochemical grafting and click chemistry for the first part of the work and the second part involved the conjugation of the synthesised QDs and the phthalocyanine by click chemistry. This approach of conjugating these nanostructures introduced another aspect of novelty to the work reported in this thesis. The immobilisation of this conjugate on a glassy carbon electrode (GCE) was achieved by adsorption. Characterisation techniques such as infrared spectroscopy, x-ray diffractometry, UV/vis spectroscopy, transmission electron microscopy and x-ray photoelectron spectroscopy were used to characterise the molecules and conjugates of interest. With respect to the electrocatalytic part of the work, electrode surface characterisation involved scanning electrochemical microscopy and cyclic voltammetry to determine changes in the nature of the surface as well as reactivity of the surface at different modification steps. Detection limits and the sensitivity determined for the electrocatalysts fabricated here proved to be an improvement compared to other reported work involving phthalocyanines and the test analytes chosen for application. With respect to the conjugate, the electrocatalytic ability was improved when the QDs and phthalocyanine were combined using click chemistry compared to using the phthalocyanine alone.
- Full Text:
- Date Issued: 2016
Foundation phase male student-teacher’s experiences during teaching practice: implications for initial teacher training
- Authors: Makeleni, Sive
- Date: 2016
- Subjects: Student teaching -- South Africa Teachers -- Training of -- South Africa Teaching -- South Africa
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/4780 , vital:28519
- Description: The aim of this study was to explore experiences of Foundation Phase male student teachers during teaching practice. Four Bachelor of Education Foundation Phase male student-teachers were selected for the purpose of this study. Venturing of males in Foundation Phase specialisation is phenomenon. Foundation Phase has been viewed as a female territory for many years. As a result, there are few males teaching in FP. The study employed the qualitative approach as a suitable approach. As the study sought to explore experiences, a phenomenological design was followed. In a true phenomenological design, unstructured interviews and personal diaries are used for data collection. In this study data were collected through unstructured interviews and personal diaries of the participants. I employed interpretivism as a research paradigm.
- Full Text:
- Date Issued: 2016
- Authors: Makeleni, Sive
- Date: 2016
- Subjects: Student teaching -- South Africa Teachers -- Training of -- South Africa Teaching -- South Africa
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/4780 , vital:28519
- Description: The aim of this study was to explore experiences of Foundation Phase male student teachers during teaching practice. Four Bachelor of Education Foundation Phase male student-teachers were selected for the purpose of this study. Venturing of males in Foundation Phase specialisation is phenomenon. Foundation Phase has been viewed as a female territory for many years. As a result, there are few males teaching in FP. The study employed the qualitative approach as a suitable approach. As the study sought to explore experiences, a phenomenological design was followed. In a true phenomenological design, unstructured interviews and personal diaries are used for data collection. In this study data were collected through unstructured interviews and personal diaries of the participants. I employed interpretivism as a research paradigm.
- Full Text:
- Date Issued: 2016
- «
- ‹
- 1
- ›
- »