Abstract To achieve high photocatalytic activity, the sizes of photocatalysts are usually reduced to nanoscales. However, nano-sized particles are difficult to be separated and recycled. In this paper, we successfully fabricate stannous oxalate microcrystals with selectively exposed facets and various morphologies (prismoids, tubes, rods and needles). The photocatalytic activities are comparative or even higher than that of commercial Degussa P25 nano titanium dioxide under both full spectrum light and ultra-violet irradiation, even though the stannous oxalate particles are in micrometer size. The exposure of { 1 ¯ 01} polar facets could drive photogenerated charge separation, and thus accelerates photocatalysis. The photocatalytic activities of the optimized sample (fragmented prismoids) with specific surface areas about 1.18 m2/g are 2.49 and 2.67 times higher than that of the commercial Degussa P25 nano titanium dioxide (specific surface areas: 48.59 m2/g) under both full spectrum light and ultra-violet irradiation in methyl orange degradation, respectively. The micro/submicron-sized particles could be easily separated and recycled after waste water treatment, and catalysts can be synthesized with a large amount by a facile chemical precipitation method. Given these factors, micro/submicron sized stannous oxalate catalysts are expected to be a practical water cleaner.

中文翻译：

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具有选择性暴露面和低比表面积的形态依赖性高活性微晶草酸亚锡光催化剂

摘要 为了实现高光催化活性，光催化剂的尺寸通常减小到纳米级。然而，纳米尺寸的颗粒难以分离和回收。在本文中，我们成功地制造了具有选择性暴露面和各种形态（棱柱形、管形、棒形和针形）的草酸亚锡微晶。尽管草酸亚锡颗粒为微米级，但在全光谱光和紫外线照射下，其光催化活性与商用德固赛 P25 纳米二氧化钛相当甚至更高。{ 1 ¯ 01} 极性面的暴露可以驱动光生电荷分离，从而加速光催化。比表面积约为 1.18 m2/g 的优化样品（碎片棱柱体）的光催化活性分别为 2.49 和 2。在全光谱光和紫外线照射下，甲基橙降解率分别比商用德固赛 P25 纳米二氧化钛（比表面积：48.59 m2/g）高 67 倍。废水处理后微/亚微米级颗粒易于分离和回收，催化剂可以通过简便的化学沉淀法大量合成。鉴于这些因素，微米/亚微米尺寸的草酸亚锡催化剂有望成为一种实用的水清洁剂。催化剂可以通过简便的化学沉淀法大量合成。鉴于这些因素，微米/亚微米尺寸的草酸亚锡催化剂有望成为一种实用的水清洁剂。催化剂可以通过简便的化学沉淀法大量合成。鉴于这些因素，微米/亚微米尺寸的草酸亚锡催化剂有望成为一种实用的水清洁剂。