Silica-gel particles were functionalized with N,N'-bis(2-phosphoethyl)-1,4,5,8-naphthalene diimide (DPN) and mesotetra(4-sulfonatophenyl) porphyrin (TSPP), by using phosphonate/sulfonate zirconium chemistry. The properties of the bound chromophores were shown to differ from their solution properties, with propensity to form either excimer or aggregates at the silica-gel surface for DPN and TSPP, respectively.