Abstract

Titania semiconductor is being used in a wide range of fields; however, the poor surface properties and meagre visible light absorption capacity of it stand as barriers for being used as an effective visible light active photocatalyst. To overcome these limitations, various strategies have been adopted, among which the usage of templates has been the topic of research for the past 10 years. Usage of the template during the synthesis of titania increases the surface area by reducing the agglomeration of nanoparticles and also shifts the absorption edge to the visible range. Nowadays, green synthesis has gained substantial attention as an effective, safe and environmentally friendly practice for the synthesis of nano-titania. Bio-waste pista shells, corn pith, and tamarind seeds which are regarded as unproductive have been used in the sol–gel synthesis of Pista Shell Templated Titania (PST), Corn Pith Templated Titania (CPT) and Tamarind Seed Templated Titania (TST). The synthesized templated titania was subjected to morphological, crystallite, surface characteristic and photocatalytic studies. XRD results of synthesized CPT, PST and TST exhibited that they possessed anatase form. The crystallite size of PST, CPT and TST was found to be 12.26 nm, 12.28 nm and 15.55 nm, respectively, proving the reduction in crystallite size than in non-templated titania. Efficient photocatalytic activity of templated titania was observed via the degradation of methyl orange, which proved the larger surface area of templated titania than that of non-templated titania. Pista shells, corn pith and tamarind seeds were found to grant a decisive support in the controlled growth of titania and in photocatalytic applications which stands out as a reason to be looked upon as an effective bio-waste green template in the synthesis of nano-titania.

Graphic abstract

中文翻译：

---

以生物废料为模板的纳米二氧化钛的简便绿色路线溶胶-凝胶合成

摘要

二氧化钛半导体被广泛应用于各个领域。然而，其差的表面性能和微弱的可见光吸收能力成为了用作有效的可见光活性光催化剂的障碍。为了克服这些局限性，已经采取了各种策略，其中，模板的使用已成为过去十年的研究主题。在二氧化钛的合成过程中使用模板可通过减少纳米颗粒的团聚来增加表面积，并将吸收边缘移至可见范围。如今，作为一种有效，安全和环保的纳米二氧化钛合成方法，绿色合成受到了广泛的关注。生物废渣皮，玉米髓，ista豆和罗望子种子被认为是无用的，已用于溶胶-凝胶法合成Pista壳模板二氧化钛（PST），玉米髓模板二氧化钛（CPT）和罗望子种子模板二氧化钛（TST）。对合成的模板二氧化钛进行了形态，微晶，表面特性和光催化研究。合成的CPT，PST和TST的XRD结果表明它们具有锐钛矿形式。发现PST，CPT和TST的微晶尺寸分别为12.26nm，12.28nm和15.55nm，证明了微晶尺寸比未模板的二氧化钛减小。通过甲基橙的降解观察到模板化二氧化钛的有效光催化活性，这证明了模板化二氧化钛的表面积大于非模板化二氧化钛的表面积。Pista贝壳，

图形摘要