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Recycling of Photovoltaic Cells and other Si, Ge Elecronic Waste.

SYSNO ASEP	0510208
Document Type	C - Proceedings Paper (int. conf.)
R&D Document Type	O - Ostatní
Title	Recycling of Photovoltaic Cells and other Si, Ge Elecronic Waste.
Author(s)	Bumba, Jakub (UCHP-M)_SAI Dřínek, Vladislav (UCHP-M)_{RID, ORCID, SAI} Fajgar, Radek (UCHP-M)_{RID, ORCID, SAI} Kaštánek, František (UCHP-M)_{RID, SAI, ORCID} Šolcová, Olga (UCHP-M)_{RID, ORCID, SAI}
Article number	082
Source Title	Proceedings Sardinia 2019. - Padova : CISA Publisher, 2019
Number of pages	6 s.
Publication form	Medium - C
Action	International Waste Management and Landfill Symposium /17./
Event date	30.09.2019 - 04.10.2019
VEvent location	Cagliari
Country	IT - Italy
Event type	EUR
Language	eng - English
Country	IT - Italy
Keywords	electronic waste recycling ; silicon ; germanium
Subject RIV	CI - Industrial Chemistry, Chemical Engineering
OECD category	Chemical process engineering
R&D Projects	TN01000048 GA TA ČR - Technology Agency of the Czech Republic (TA ČR)
Institutional support	UCHP-M - RVO:67985858
Annotation	New technology for electronic waste recycling to produce ultrapure silicon, germanium or CVD precursors was thoroughly studied, designed and verified. The three-step-process is based on low-temperature synthesis of magnesium silicide (Mg2Si) and/or germanide (Mg2Ge) directly from end-of-life photovoltaic cells and waste magnesium chips in the case of magnesium silicide and from broken germanium optical lenses and magnesium chips in the case of magnesium germanide preparation. The prepared products were characterised by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Spectroscopy (EDX) and Raman spectroscopy, which confirmed high conversion to desired products, its good crystallinity and also homogeneity. Prepared samples were then hydrolysed by phosphoric acid solution to produce silicon and/or germanium hydrides. Their presence was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography–Mass Spectroscopy (GC-MS). In the next step, it was also tested that silicon and also germanium hydrides are relatively instable to the point that they can be easily decomposed into ultrapure elements Si, Ge and hydrogen. Additionally, it is possible to use them as desirable precursors for the preparation of thin silicon and germanium layers or for the synthesis of metal silicides and germanides by Chemical Vapour Deposition (CVD) methods. The thin semiconductive layers are commonly used in microelectronic industry, while metal silicides and germanides could find potential use in the field of catalysis, thermoelectricity and electronics. The only by-product of the whole process, magnesium phosphate, can be used as a fertilizer.
Workplace	Institute of Chemical Process Fundamentals
Contact	Eva Jirsová, jirsova@icpf.cas.cz, Tel.: 220 390 227
Year of Publishing	2020
Electronic address	http://hdl.handle.net/11104/0300740

Number of the records: 1