Cavity-confined acceleration of iron cycle for the Fenton-like reaction by β-CD-benzoquinone host–guest complex under visible irradiation

• Published in: Catalysis communications 2015-05, Vol.65, p.96-101
• Main Authors: Fu, Liting, Zhao, Zhenwen, Ma, Jiahai, Hu, Xuefeng
• Format: Article
• Language: English
• Subjects: Fenton; Host–guest complex; Iron cycle; Visible irradiation
• ISSN: 1566-7367; 1873-3905
• DOI: 10.1016/j.catcom.2015.02.012

The catalyst (CDBQ) that was prepared from β-cyclodextrin (β-CD) and 2,5-dihydroxy-1,4-benzoquinone (2,5-DBQ) achieved the cavity-confined acceleration of iron cycle under visible irradiation. The semi-quinone-like (SQ) radical was generated from photoexcitation of 2,5-DBQ within the β-CD's cavity. The SQ radical as an electron donor could coordinate with iron ions, and thus 2,5-DBQ shuttled one electron between Fe3+ and Fe2+ via Fe–dihydroxybenzoquinone complex process. In Fenton reactions, CDBQ greatly increased the HO yield, and thus significantly accelerated the degradation of dyes. The cavity-confined acceleration of iron cycle has promising applications in photo-Fenton system for the efficient decontamination for wastewater. [Display omitted] •β-CD-benzoquinone (CDBQ) was readily prepared as cavity-confined co-catalyst.•CDBQ efficiently accelerated Fe2+/Fe3+ cycle under visible irradiation.•The semi-quinone-like radical as an electron donor could coordinate with iron ions.•The redox of Fe2+/Fe3+ with quinones occurred within the β-CD's cavity.•The cavity-confined acceleration has promising applications in photo-Fenton system.