Abstract

Photocatalysts in powder form commonly cannot have a high photocatalytic efficiency without strong agitation in traditional photocatalytic process. It is also inconvenient for recovery of the photocatalysts in powder form after usage. This consequently, results in a secondary pollution which limits their application in water treatment for heavily polluted natural waterways. In this work, coating GO and TiO₂ nanomaterials over large-scale cellulose substrates which can easily float on water was performed in the presence of crosslinker by applying a simple dip-coating method. The photocatalytic activities were evaluated by studying the degradation of two models of organic pollutants, methylene blue and glyphosate under visible light irradiation. The nanomaterial wrapped substrates endured over 40 times reuse at an optimum photocatalyst concentration of 0.1 g/L GO and 15% TiO₂ based on fabric weight. The highest degradation rate was obtained at this point and a further increase in concentration decreased the degradation rate. The efficient degradation of glyphosate by the nanomaterial loaded substrate confirms its industrial application in treating pesticide and herbicide polluted waters. Remarkably, this study has established a feasible practical way for direct degradation of pollutants in lakes or rivers using mechanically floating large-scale cellulose-supported photocatalysts.

Graphic abstract

中文翻译：

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基于石墨烯/ TiO 2纳米涂层的多功能纤维素织物的制备

摘要

在传统的光催化方法中，如果没有强烈搅拌，粉末状的光催化剂通常不能具有高的光催化效率。使用后以粉末形式回收光催化剂也是不方便的。因此，这导致了二次污染，从而限制了它们在严重污染的天然水道的水处理中的应用。在这项工作中，涂覆GO和TiO ₂通过使用简单的浸涂方法，在交联剂存在的情况下，可以在水上容易漂浮的大规模纤维素基材上制备纳米材料。通过研究可见光照射下亚甲基蓝和草甘膦这两种有机污染物的降解来评估光催化活性。纳米材料包裹的基材在0.1 g / L GO和15％TiO ₂的最佳光催化剂浓度下可重复使用40次以上根据织物的重量。此时获得最高的降解速率，并且浓度的进一步增加降低了降解速率。纳米材料负载的基质对草甘膦的有效降解证实了其在处理农药和除草剂污染的水中的工业应用。值得注意的是，这项研究已经建立了一种可行的实用方法，可以使用机械漂浮的大型纤维素负载型光催化剂直接降解湖泊或河流中的污染物。

图形摘要