Preparation of transparent Mn-doped CaF2 glass-ceramics from silicon-manganese slag: Dependence of colour-controllable change on slag addition and crystallization behavior

Silicon-manganese slag was firstly used to prepare the transparent colour-controlled glass-ceramics containing Mn-doped CaF2 nanocrystals. The maximum utilization ratio of slag reaches to 27.04 wt%, and the colour of the samples trended red-brown to red light as the added slag content increased. The transparent glass-ceramics could be prepared when crystallized between 650 and 710 degrees C for 2 h, and had a minimum transmittance of 67.95 % at a wavelength of 780 nm. Increasing the content of added slag caused the emission spectrum to shift, demonstrating the ability to control the colour of the transparent glass-ceramics, and also enhanced the fluorescence intensity. The crystallization behaviour conversely has little effect on the colour change, but can increase the fluorescence intensity. In general, this work provides a new approach for the comprehensive utilization of silicon-manganese slag for applications in optical engineering.