We report the synthesis of Cr-doped silica with different morphologies by sol-gel polymerization of tetraethoxysilicate in the presence of D-sorbitol derived organogelators (1,3:2,4-bis-O-benzylidene-D-sorbitol, DBS and its p-nitro and p-methoxy derivatives) and hexadecyltrimethylamonium bromide with S-(+)-1-phenylethylamine-tricarbonyl-chromium, acting both as chiral catalyst and source of chromium, for a 10 wt% Cr/SiO2 loading. Two different types of morphologies were observed: silica tubes with 300-500nm diameter and 10-15μm length for the nitro-substituted template and “necklace” type agglomerated silica granules for the other templates. EDX and XPS analyses revealed a uniform distribution of Cr ions on silica matrix consisting of 80% Cr3+ and 20% Cr6+.

 

 

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