Synergy between Platinum and Gold Nanoparticles in Oxygen Activation for Enhanced Room‐Temperature Formaldehyde Oxidation. (30th December 2021)

• Record Type: Journal Article
• Authors: Ye, Jiawei; Zhu, Bicheng; Cheng, Bei; Jiang, Chuanjia; Wageh, S.; Al‐Ghamdi, Ahmed A.; Yu, Jiaguo
• Is Part Of: Advanced functional materials. Volume 32:Number 15(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-30
• Subjects: active oxygen -- HCHO oxidation -- negatively charged Pt -- Pt–Au bimetal -- synergistic effects; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202110423
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Room‐temperature oxidation over supported noble metals provides a feasible approach to eliminating formaldehyde (HCHO) from indoor air. Oxygen activation by noble metals such as gold and platinum plays a key role in achieving complete HCHO oxidation, but it is unclear how different noble metals function synergistically toward oxygen activation. Here, the synergistic mechanisms of Pt and Au nanoparticles (NPs) coloaded on TiO2 in catalytic HCHO oxidation are elucidated. Strikingly, ≈0.08% doping of Pt can dramatically improve the catalytic activity of 0.9% Au/TiO2 . The surface oxygen species of TiO2 jointly activated by Au and Pt NPs can rapidly transform HCHO to dioxymethylene surface species, while negatively charged Pt NPs can efficiently adsorb and activate molecular oxygen to oxidize the dioxymethylene into formate, which is further completely oxidized. This synergy enables efficient HCHO oxidation at surface sites between adjacent Pt and Au NPs. Abstract : The synergy of Pt and Au jointly activates surface oxygen to adsorb and convert formaldehyde into dioxymethylene (DOM), preventing formaldehyde from occupying Pt sites and enabling Pt to activate O2 continuously to oxidize DOM into formate. Ultrahigh formate concentration accelerates the rate‐determine step: HCOO * + OH * → CO2 + H2 O, and opens the decomposition pathway: HCOO * → CO + OH * .