Photocatalytic ability of visible-light-responsive hybrid ZrO2 particles

The interfacial charge transfer (ICT) complex formation between zirconium dioxide (ZrO2), the material absorbing below 250 nm, and 5-aminosalicylic acid (5-ASA) leads to the formation of visible-light-absorbing inorganic-organic hybrids. The free amino groups, present on the hybrid's surface after the ICT complex formation, were used to reduce silver ions and link silver particles to ZrO2. The prepared samples were characterized by using transmission electron microscopy, X-ray diffraction analysis, and nitrogen adsorption-desorption isotherms. Density functional theory (DFT) calculations using a cluster model are applied to explain optical changes in hybrids, i.e., absorption redshift induced by the ICT complex formation. Decolorization of an organic dye crystal violet (CV), under ultraviolet-C or visible light, was used to compare the photocatalytic ability of the prepared samples. The ICT complex formation transformed ZrO2 into a hybrid material able to induce photocatalytic reactions under exclusive visible light excitation.