Non-oxide supported Pt-metal-group catalysts for efficiently CO and toluene co-oxidation: Difference in water resistance and degradation intermediates

Herein, Pd and Pt-catalysts loaded on non-oxide support (g-C3N4) were prepared and compared for CO and toluene co-oxidation, and Pt/C3N4 presented excellent catalytic performance. A series of characterizations including TEM, H2-TPR, O2-TPR and XPS etc., indicated that Pt/C3N4 exhibited the smaller Pt NPs, better low temperature reduction ability, more active oxygen species and positive charged Pt species, which could account for its better catalytic performance. Additionally, DFT calculations further confirmed that the lower activation barrier of O2 and the higher adsorption for CO and toluene triggered the efficient CO and toluene degradation over Pt/C3N4. Interestingly, the introduction of H2O (10.0 vol%) suppressed the catalytic performance of Pd/ C3N4, while expedited CO and toluene oxidation over Pt/C3N4, which was revealed by DFT calculations. Furthermore, the difference in degradation intermediates, corresponding distributions and toxicity generated during toluene oxidation under different conditions over Pd/C3N4 and Pt/C3N4 were exposed. Compared with Pd/C3N4, less variety, toxicity and content of intermediates produced over Pt/C3N4. This work would inspire many rational designs of supported noble metal catalysts for environmentally friendly catalysis.

Automated summary

In this study, Pd and Pt catalysts loaded on non-oxide support (g-C3N4) were compared for CO and toluene co-oxidation, and Pt/C3N4 showed superior catalytic performance. Various characterizations and DFT calculations revealed that Pt/C3N4 had smaller Pt nanoparticles, better reduction ability, more active oxygen species, and positively charged Pt species, which contributed to its enhanced catalytic performance. The introduction of H2O suppressed the catalytic performance of Pd/C3N4 but expedited CO and toluene oxidation over Pt/C3N4, as confirmed by DFT calculations. The difference in degradation intermediates, distributions, and toxicity between Pd/C3N4 and Pt/C3N4 during toluene oxidation under different conditions was also revealed.