State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350116, PR China.
State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350116, PR China.
J Colloid Interface Sci. 2023 Mar;633:323-332. doi: 10.1016/j.jcis.2022.11.120. Epub 2022 Nov 26.
Photoanodic hydrogen peroxide (HO) production via water oxidation is limited by low yields and poor selectivity. Herein, four variations of cobalt phosphides, including pristine CoP and CoP crystals, and two mixed-phase cobalt phosphides (CoP/CoP) with different ratios, were applied as co-catalysts on the BiVO (BVO) photoanode to improve HO production. The optimal yield and selectivity were approximately 9.6 µmol‧h‧cm and 25.2 % at a voltage bias of 1.7 V vs reversible hydrogen electrode (V) under sunlight illumination, respectively. This performance is approximately 1.8 times that of pristine BVO photoanode. The roles of the Co and P sites were investigated. In particular, the Co site promotes the breaking of one HO bond in water to form OH radicals, which is the rate-determining step in HO production. The P site plays an important role in the desorption of HO formed from the catalyst, which is responsible for the recovery of fresh catalytic sites. Among the four samples, CoP exhibited the best performance for HO production because it had the highest rate of OH formation owing to its improved accumulation property. This study offers a rational design strategy for co-catalysts for photoanodic HO production.
通过水氧化进行光阳极过氧化氢 (HO) 的产生受到产率低和选择性差的限制。在此，将四种不同的磷化钴变体，包括原始的 CoP 和 CoP 晶体，以及两种具有不同比例的混合相钴磷化物 (CoP/CoP)，用作 BiVO（BVO）光阳极的共催化剂，以提高 HO 的产生。在 1.7 V 偏压下（相对于可逆氢电极 (V)），在阳光照射下，最佳产率和选择性分别约为 9.6 µmol·h·cm 和 25.2%。这一性能大约是原始 BVO 光阳极的 1.8 倍。研究了 Co 和 P 位的作用。特别是，Co 位促进水中断裂一个 HO 键形成 OH 自由基，这是 HO 产生的速率决定步骤。P 位在 HO 从催化剂中解吸中起着重要作用，这对于恢复新鲜的催化位点是必需的。在这四种样品中，CoP 表现出最好的 HO 产生性能，因为由于其改善的积累特性，其 OH 形成率最高。这项研究为光阳极 HO 产生的共催化剂提供了合理的设计策略。
