Cerium and boron chemistry in doped borosilicate glasses examined by EELS

Various transmission electron microscopic techniques to characterize phase separation – illustrated using a LaF3 containing aluminosilicate glass

“…So the droplet-like dark regions (around 10-15 nm size range) in this image are the regions where the element which has the highest atomic number among the constituents of this glass material is accumulated. Among all elements contained in this glass, lanthanum has the highest atomic number (57) while Si (14), Al (13), Na (11), F (9), and O (8) possess much smaller atomic numbers then La. Therefore, it can be concluded that these dark regions correspond to a La-rich phase.…”

“…In general, glasses possessing higher contents of alkali ions use to be critical in this respect. Also borosilicate glasses prove very sensitive towards irradiation with highenergy electron beams [13], but nevertheless spatially resolved measurements of boron coordination are possible with enhanced efforts [14].…”

Nano-scale quasi-melting of alkali-borosilicate glasses under electron irradiation

“…Most probably we observed the spinodal phase separation in silica-rich and alkali-borate rich phases such as that which occur in ''Vycor"-type glasses, a process that typically requires temperatures above 700°C and times of the order of several hours [28]. Note that additionally visible Ce-oxide nanophases, formed during cooling and described in detail in [27] do not participate in this transformation. The picture is valuable as it clearly excludes temperature rise as the main reason for either effects of shape transformation or phase separation.…”

“…The glasses studied in this work have been melted as described before [25,27], to result in compositions of Table 1, where ''glass A" is a Ca-alumino-borosilicate, and ''glass B" is a Li-Na Borosilicate (with Ce-Zr-Cr-doping).…”

Graphite immobilisation in iron phosphate glass composite materials produced by microwave and conventional sintering routes

“…For example, borosilicate glasses are used in France and the UK for the immobilisation of HLW [15]. A number of borosilicate glasses for the immobilisation of HLW have been developed and information regarding the processing characteristics, corrosion behaviour, mechanical performance, thermal stability as well as radiation stability is widely available [16,17]. However, the use of conventional melting and/or heating in glass processing is potentially problematic due to oxidation of the graphite.…”