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Herein, nanoporous silica monoliths are used as a morphological template for liquid‐phase synthesis of luminescent carbon nanodots. Two kinds of sol–gel‐derived porous silica samples with the average nanopore sizes of 40 and 7 nm are infiltrated with sucrose/dimethyl sulfoxide solution followed by thermolysis at 170–180 °C. Thermal treatment causes the formation of carbon moieties that are, afterward, extracted into water. The obtained aqueous solutions of carbon dots show intense photoluminescence. The observed emission and excitation bands are strongly affected by the morphology of nanoporous silica template. Larger pore size of silica nanotemplate results in the red shift of the emission and excitation bands. [ABSTRACT FROM AUTHOR]

The effect of hydration procedure of fumed silica precursor on photoluminescent properties of carbonized silica (SiO2:C) nanocomposite after chemo/thermal treatments is studied. Main structural effect is the formation of chemical bonding of phenyl groups to silica surface via multiple CSiO bonding bridges. Synthesized samples demonstrate very broad photoluminescence (PL) bands in near ultraviolet and visible ranges with maximum intensity dependent on temperature of thermal annealing. Two main trends in luminescence properties are: 1) hydration‐induced blue shift of PL in comparison with PL of unhydrated series; 2) red shift of PL bands with increasing synthesis temperature regardless hydration procedure. Temperature dependent evolution of light emission bands is discussed in terms of surface carbon nanoclusters formation and aggregation processes. It is assumed that blue shift of PL bands in the hydrated series is associated with the decreased surface mobility of carbon atoms and clusters as a result of increased chemical bonding with silica surface that slows down carbon thermally stimulated clusterization/aggregation processes. Broad band photoluminescence of carbon nanoprcipitates dispersed in fumed silica is studied. The effects of silica surface pretreatment and pyrolysis of PhTMS grafted to silica surface on near UV and VIS emission are discussed in term of surface mobility and surfac. [ABSTRACT FROM AUTHOR]