https://www-elplural-com.translate.goog/el-telescopio/tech/universidad-de-cordoba-grafeno-luz-tecnologia-informatica-smartphone_215304102_amp?_x_tr_sl=es&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=ajax,se,elem
Found this earlier in the Spanish 5th Column site, graphene oxide can have luminescent properties also…..