Trace Amount of SnO₂-Decorated ZnSn(OH)₆ as Highly Efficient Photocatalyst for Decomposition of Gaseous Benzene: Synthesis, Photocatalytic Activity, and the Unrevealed Synergistic Effect between ZnSn(OH)₆ and SnO₂

Abstract

It is still a challenge to develop a high performance photocatalyst for the abatement of aromatic compounds like benzene (C6H6) that has been regarded as a priority hazardous VOC substance in the indoor atmosphere. Zinc hydroxystannate (ZnSn(OH)6, ZHS) is a promising material for the application. However, the key structural features which responsible for the high activity are still ambiguous. To address this issue, a series of ZHS with different surface properties was hydrothermally synthesized by varying the treatment temperature and the solution pH. Although ZHS can be readily synthesized under a mild reaction condition (Tem. 90-120 o C, pH 4-10), most of the samples were contaminated by trace amount of low-crystalized SnO2. Pristine ZHS can only be produced in a strong alkaline solution (pH 13). The sample prepared at 120 o C in a pH 10 solution shows the highest activity for the degradation of gaseous C6H6 and the efficiency almost six times higher than P25 (TiO2). More importantly, no obvious deactivation of the sample and the formation of stable deposits were observed in a long-term reaction for 48 h.Although SnO2 amount is quite small and bare ZHS shows almost no activity, both of them are indispensable for the degradation of C6H6. SnO2 and ZHS can be understood as photoactive sites to produce charge carriers and preferential sites for the adsorption of O2, H2O, and C6H6, respectively. A synergistic effect between SnO2 and ZHS in the formation of active radicals and the degradation of C6H6 accounts for the high performance of the SnO2 decorated ZHS.

One-pot hydrothermal synthesis of highly efficient SnOx/Zn2SnO4 composite photocatalyst for the degradation of methyl orange and gaseous benzene

“…Although ZTO shows the highest efficiency for C6H6 conversion, the mineralization of C6H6 is only 60.4%. Consistent with the reported works [42,60], P25 shows low activity for the degradation of gaseous C6H6 and the C% of C6H6 is only 9.6%.…”

“…As shown in Fig. 7 The mineralization of C6H6 on P25 is not as significant as the decoloration of MO and a color change of P25 from white to slight brown has been observed suggesting the deposition of intermediates [42,60]. ZTO shows the highest mineralization rate of C6H6 and the average rate is 62.1 μmol·h −1 ·g −1 .…”

“…The work [60]. Although ZTO shows the highest efficiency for C6H6 conversion, the mineralization of C6H6 is only 60.4%.…”

Hierarchical h-, m- and n-BiPO4 microspheres: facile synthesis and application in the photocatalytic decomposition of refractory phenols and benzene

“…[7][8][9] To solve the problem, exploitation of new photocatalysts with excellent activity is one of the developing directions of photocatalysis. [10][11][12] In numerous photocatalysts, BiPO 4 has drawn much great attention in recent years. [13][14][15][16][17][18][19][20][21][22][23][24] For example, Zhu's group 13 reported that the photocatalytic activity of BiPO 4 is superior to P25 (TiO 2 , Degussa) under UV light irradiation.…”

Facile fabrication of ZnO/N‐doped helical carbon nanotubes composites with enhanced photocatalytic activity toward organic pollutant degradation

“…TiO 2 , ZnO, SnO 2 , etc.) for photocatalytic applications, zinc oxide (ZnO) has grown considerably, due to its physical and chemical stability, high catalytic activity, low cost, environmental friendliness and easy of availability . However, enhancing the photocatalytic efficiency of ZnO to meet the practical application requirements is still a challenge because of the bottleneck of poor quantum yield caused by the rapid recombination of photogenerated electrons and holes .…”