【作者】 刘辉晖；

【导师】 范同祥；

【作者基本信息】 上海交通大学 ， 材料学， 2011， 硕士

【摘要】 能源与环境危机是21世纪人类面临的巨大挑战,充分利用太阳能是应对这一挑战的有效方法。蝶类在几千万年的自然选择中进化出了非常精美的鳞片微结构来与太阳光相互作用。通过借鉴大自然中蝶翅鳞片的精妙结构,将其与半导体光催化剂所具有的光催化性能巧妙的相互耦合,可以得到光催化性能更好的生物分级构造光催化剂,从而为充分利用太阳能解决能源与环境问题提供新的设计思路。本文选取了凤蝶科的玉斑凤蝶(Papilio helenus Linnaeus)、绿带翠凤蝶(Papilio maackii)以及斑蝶科的异型紫斑蝶(Euploea mulciber)共三种不同宏观和微观形貌的蝴蝶,以三氯化钛溶液作为前躯体,使用“浸渍-煅烧”法制备了三种不同蝶翅模板的生物分级构造二氧化钛。通过XRD、FESEM、TEM、氮吸附以及UV-Vis等方法对所得产物进行了晶相与晶粒度、微观结构、孔径与孔分布以及光捕获性能等一系列表征,结果表明产物均为晶粒细小均匀的单一锐钛矿相二氧化钛,具有适当缩小的蝶翅模板的脊-孔介孔分级结构,同时产物还具有均匀分布的微孔结构,微孔孔径约为8 nm左右、分布集中,相比无模板二氧化钛,玉斑凤蝶模板生物分级构造二氧化钛和异型紫斑蝶模板生物分级构造二氧化钛在波长小于380 nm的紫外光区光捕获性能分别提高了35%左右,绿带翠凤蝶模板生物分级构造二氧化钛在波长小于380 nm的紫外光区光捕获性能提高了20%左右。对三种不同蝶翅模板的生物分级构造二氧化钛进行了光催化降解结晶紫实验,并在此基础上以光催化降解结晶紫效果最好的玉斑凤蝶蝶翅结构二氧化钛为例进行了光解水制氢性能研究光催化分解水制氢实验,从而测试其光催化性能,结果表明所得生物分级构造二氧化钛可以成功的将结晶紫大分子共轭体系破坏,将其降解为水、二氧化碳及其他无污染性的有机小分子;相比无模板二氧化钛,三种生物分级构造二氧化钛光催化降解结晶紫的效率分别提高了4.3倍、2.6倍和1.9倍;相比无模板二氧化钛,同样的条件下,生物分级构造二氧化钛的光催化分解水效率提高了7倍左右;沉积1.5% Pt的生物分级构造二氧化钛的产氢效率是沉积1.5% Pt的无模板二氧化钛的2.24倍左右。本研究巧妙的借鉴了大自然中蝶翅的精细结构并加以利用,实现了天然生物结构与半导体光催化剂所具有的光催化性能的巧妙耦合,为探索新型功能材料提供了新的设计思路。更多还原

【Abstract】 The world’s energy crisis and environmental problems continue to grow as civilization continues. Using photocatalyst to make use of solar energy seems to be a promising solution. Butterfly wings have a lot of periodical submicrometer structures in their scales coming from millions of years of evolution. Here we put forward a general strategy of borrowing nature’s butterfly wing hierarchical architecture to get better photocatalytic performance of TiO2, a typical sunlight water splitting photocatalyst. This concept is of certain potential to be extended to many other relative species, thus give a broad scope of building prototypes to exploit solar energy for sustainable energy resources.Three kinds of butterflies: Papilio helenus Linnaeus、Papilio maackii&Euploea mulciber were chosen as bio-template. Bio-inspired hierarchical TiO2 samples were synthesized by a immersing-calcine method using TiCl3 solutions as precursor.Several kinds of characterizing methods like XRD, FESEM, TEM, UV-Vis Absorption were employed to characterize the products. The products are identified as being due to the anatase phase of TiO2, and their average grain size is about 10 nm. The mesoporous architectures from original butterfly wing scales were well borrowed with a proper size shrank. The products also have nanoporous architectures and the average pore size is about 8 nm. Compared to TiO2 made by the same method but without template, light harvesting efficiency of bio-inspired hierarchical TiO2 was enhanced by about 20 -35percent in wave range of about 380nm to 200nm.Experiments of organic dyes degradation under a 500W Xe lamp indicate that the photocatalytic activity of bio-inspired hierarchical TiO2 samples are 4.3, 2.6, and 1.9 times superior than that of TiO2 made by the same method but without template respectively. And H2 production performance in sunlight driven water splitting indicate that the photocatalytic activity of bio-inspired hierarchical TiO2 is 7 times superior than that of TiO2 made by the same method but without template, 2.24 times when both samples were loaded with 1.5wt.% Pt.更多还原