Manufacturing hydrogen peroxide from both photocatalytic oxygen reduction and water oxidation availed by bismuth yttrium oxyhalide

Photocatalytic H 2 O 2 production still confronts the challenges of its dependence on organic electron donors or high-purity O 2 , which restricts the practical application, and there are few studies on the photosynthesis of H 2 O 2 via both oxygen reduction reaction (ORR) and water oxidation reaction (WOR). In this paper, bismuth yttrium oxyhalides Bi 2 YO 4 X (X = Cl, Br, or I) are demonstrated to afford sufficient driving forces to produce H 2 O 2 in the absence of sacrificial reagents. After modification with Pt and IrO 2 as cocatalysts, which can selectively promote both ORR and WOR reactions on Bi 2 YO 4 Cl, the IrO 2 -Pt/Bi 2 YO 4 Cl sample yields H 2 O 2 production activity of 647 µmol L −1 h −1 with negligible decay in the long-term reaction using only H 2 O and an air atmosphere as the electron donors and O 2 source. Detailed characterizations reveal that the ORR reaction obeys a two-electron pathway. We present the first example of oxyhalides (Bi 2 YO 4 X) capable of efficient photocatalytic H 2 O 2 generation with record-breaking activity.