Institute of Materials Science and Technology, Friedrich-Schiller-University of Jena, Löbdergraben 32, 07743 Jena, Germany.
Langmuir. 2012 Sep 18;28(37):13518-25. doi: 10.1021/la302787z. Epub 2012 Sep 4.
Bacterial nanocellulose (BNC) is an extraordinary biopolymer with a wide range of potential technical applications. The high specific surface area and the interconnected pore system of the nanofibrillar BNC network suggest applications as a carrier of catalysts. The present paper describes an in situ modification route for the preparation of a hybrid material consisting of BNC and photocatalytically active anatase (TiO(2)) nanoparticles (NPs). The influence of different NP concentrations on the BNC biosynthesis and the resulting supramolecular structure of the hybrids was investigated. It was found that the number of colony forming units (CFUs) and the consumption of glucose during biosynthesis remained unaffected compared to unmodified BNC. During the formation of the BNC network, the NPs were incorporated in the whole volume of the accruing hybrid. Their distribution within the hybrid material is affected by the anisotropic structure of BNC. The photocatalytic activity (PCA) of the BNC-TiO(2) hybrids was determined by methanol conversion (MC) under UV irradiation. These tests demonstrated that the NPs retained their PCA after incorporation into the BNC carrier structure. The PCA of the hybrid material depends on the amount of incorporated NPs. No alteration of the photocatalyst's efficiency was found during repeated PCA tests. In conclusion, the in situ integration of photocatalytically active NPs into BNC represents an attractive possibility to extend its fields of application to porous filtering media for drinking water purification and air cleaning.
细菌纳米纤维素（BNC）是一种具有广泛潜在技术应用的特殊生物聚合物。纳米纤维 BNC 网络的高比表面积和相互连接的孔系统表明其可用作催化剂的载体。本文描述了一种原位改性方法，用于制备由 BNC 和光催化活性锐钛矿（TiO(2)）纳米颗粒（NPs）组成的混合材料。研究了不同 NP 浓度对 BNC 生物合成的影响以及所得混合物的超分子结构。结果发现，与未改性的 BNC 相比，生物合成过程中的菌落形成单位（CFU）数量和葡萄糖消耗保持不变。在 BNC 网络形成过程中，NP 被掺入到正在形成的混合体的整个体积中。NP 在混合材料中的分布受到 BNC 各向异性结构的影响。通过在 UV 照射下甲醇转化（MC）来确定 BNC-TiO(2) 混合物的光催化活性（PCA）。这些测试表明，NP 掺入 BNC 载体结构后保留了其 PCA。混合材料的 PCA 取决于掺入的 NPs 的量。在重复 PCA 测试过程中，未发现光催化剂效率的任何变化。总之，将光催化活性 NPs 原位整合到 BNC 中代表了一种有吸引力的可能性，可以将其应用领域扩展到饮用水净化和空气清洁用多孔过滤介质。
