Iron oxide incorporated titania nanoparticles (FIT) with various atomic ratios of Fe/Ti, i.e. 3.53% (FIT-1), 8.3% (FIT-2), and 20.79% (FIT-3), are prepared to monitor the selectivity of photo-degradation for anthranilic acid (AA) in molecular level. In the FIT-1 route, the products obtained from the photo degradation of AA are aniline, 4-aminophenol, and benzene. Since the surface of iron oxide domain in FIT-1 is fully reduced to FeO. The FeO, by trapping the photo-generated (e(-)), acts as a Lewis base to facilitate the de-carboxylation reaction for AA to create aniline. It is noteworthy that the highly alkaline surface of FIT-1 executes the hydroxylation addition for AA to produce 4-aminophenol. In FIT-2, and FIT-3 routes, the surface of incorporated iron oxide is only partially reduced to FeO. After the photo-degradation of AA, the collected products are 2-aminobenzaldehyde, and benzene. In this route, the low spin (LS) Fe3+ ion in the Fe2O3 region adopts the photo-generated (e(-)). The LS Fe3+ is reduced to stable LS Fe2+, i.e. FeO. At this stage, the Fe2O3 domain acts as a Lewis acid to push forward the carbonyl reduction of AA to obtain 2-aminobenzaldehyde. In addition, the de-amination is contributed by the nucleorphilic attack of water molecule to the carbon atom of aromatic ring bonded to NH2 group. After the de-amination reaction, the intermediate product is phenol. The following de-hydroxyl reaction by FeO domain proceeds immediately. The final product is benzene that is observed in all FIT involved catalytic routes. (C) 2015 Elsevier B.V. All rights reserved.