Dissertation/ Thesis
The photoelectronic properties of chalcogenide glass ceramic ; Les propriétés photoélectroniques de vitrocéramique de chalcogénures
| العنوان: | The photoelectronic properties of chalcogenide glass ceramic ; Les propriétés photoélectroniques de vitrocéramique de chalcogénures |
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| المؤلفون: | Xu, Yang |
| المساهمون: | Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes, Xiang Hua Zhang, Alain Lafond |
| المصدر: | https://theses.hal.science/tel-01071400 ; Material chemistry. Université de Rennes, 2014. English. ⟨NNT : 2014REN1S037⟩. |
| بيانات النشر: | HAL CCSD |
| سنة النشر: | 2014 |
| المجموعة: | Université de Rennes 1: Publications scientifiques (HAL) |
| مصطلحات موضوعية: | Chalcogenide glasses, Glass ceramic, Heterojunction, Photovoltaic effect, Photocatalysis, Verres de chalcogénures, Vitrocéramiques, Hétérojonction, Effet photovoltaïque, Photo-catalyse, [CHIM.MATE]Chemical Sciences/Material chemistry |
| الوصف: | A totally new family of glass ceramics with a unique microstructure was fabricated by controlling the crystallization of the GeSe2-Sb2Se3-CuI glass system. The influences of the material composition and the crystallizing process of the precursor glasses on the microstructure and photocurrent of the prepared glass ceramics were investigated. An optimized composition, 40GeSe2-40Sb2Se3-20CuI, was particularly studied with the following significant results: (1) After a systematic study, it was found that this particular composition shows the highest photocurrent density among all studied glasses in the pseudo-ternary GeSe2-Sb2Se3-CuI system. It is also demonstrated that the photocurrent generated by different glass ceramics is not only determined by the composition, but also by the composite microstructure of the glass ceramic, which is determined by the ceramisation process. This process was then carefully studied. Compared with the two-step heat treatment process, the single-step process at a low temperature is a more efficient strategy to build up an efficient composite microstructure, which promotes charge carrier separation and provides a conductive channel, leading to a high photocurrent intensity in the glass ceramic. (2) The above-mentioned unique composite microstructure is composed of interconnected conductive microdomains, formed by low conductive rod-like Sb2Se3 crystals, covered by relatively high conductive Cu2GeSe3 nanocrystals. The most likely process for efficient photogeneration of charges is proposed as follows: photons are efficiently and essentially absorbed by Sb2Se3 as well as by Cu2GeSe3, and then the heterojunction formed by n-type Sb2Se3 and p-type Cu2GeSe3 promotes the charge separation, whereas the oriented and relatively conductive Cu2GeSe3 aggregate provides a conductive channel and plays the role of efficient charge collector. This structure results in exceptionally long lifetime of charge carriers (around 16 µs) and high photocurrent (at least 100 times higher than any of Sb2Se3 and ... |
| نوع الوثيقة: | doctoral or postdoctoral thesis |
| اللغة: | English |
| Relation: | NNT: 2014REN1S037 |
| الاتاحة: | https://theses.hal.science/tel-01071400 https://theses.hal.science/tel-01071400v1/document https://theses.hal.science/tel-01071400v1/file/XU_Yang.pdf |
| Rights: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.27562F6C |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |