Abstract Photocatalysts based on calcined ZnAl layered double hydroxides were obtained by coprecipitation and the subsequent thermal treatments at different temperatures. The calcined materials were characterized and its photocatalytic behavior was evaluated in the water splitting reaction in presence of UV irradiation. According to the XRD analysis, there was detected the presence of Zn as hexagonal ZnO in all the samples, as well as Al forming ZnAl 2 O 4 and Zn 6 Al 2 O 9 , depending on the temperature of calcination employed. H 2 yield was higher as the annealing temperature was increased due to the formation of the heterojunctions of ZnO with the Zn 6 Al 2 O 9 and ZnAl 2 O 4 oxides, reaching the maximum value in the sample annealed at 600 °C. Some decay in the activity was observed in the sample calcined at 700 °C, probably due to the higher recombination rate of the photogenerated charge carriers in that heterojunction in comparison with that obtained at 600 °C.

中文翻译：

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使用源自煅烧的 ZnAl LDH 的光催化剂通过水分解反应产生 H2

摘要 通过共沉淀和后续不同温度的热处理，获得了基于煅烧的ZnAl层状双氢氧化物的光催化剂。对煅烧材料进行表征，并在紫外线照射下在水分解反应中评估其光催化行为。根据 XRD 分析，检测到所有样品中都存在六方 ZnO 形式的 Zn，以及形成 ZnAl 2 O 4 和 Zn 6 Al 2 O 9 的 Al，这取决于所采用的煅烧温度。由于 ZnO 与 Zn 6 Al 2 O 9 和 ZnAl 2 O 4 氧化物异质结的形成，随着退火温度的升高，H 2 产率更高，在 600 °C 退火的样品中达到最大值。在 700 °C 煅烧的样品中观察到一些活性衰减，