二氧化钛复合纸板对甲基橙水溶液的光催化降解

制备了系列植物纤维-陶瓷纤维-二氧化钛复合纸板,考察了它们对甲基橙水溶液的吸附及光催化降解件能.结果表明.二氧化钛复合纸板对甲基橙具有较好的吸附和光催化降解性能,紫外光照射面积为55 cm2的二氧化钛复合纸板2.5 h后可使15mL、浓度为25 ms/L的甲基橙水溶液的色度减小90%以上.二氧化钛复合纸板在该溶液中的稳定性好,反复使用10次,其时甲基橙的光催化降解性能不变,质量仅减小1.1%.     

纳米TiO_2光催化去除水华藻类的研究进展

由水体富营养化而引起的蓝藻水华是目前全球面临的重大水环境问题,严重威胁水生生态环境以及人类的健康。综述了近年来以TiO_2为代表的纳米材料光催化技术在蓝藻水华治理方面的研究现状,其中光催化负载体技术与可见光响应下高效光催化性能的研究广泛;归纳并总结了TiO_2抑制蓝藻生长光催化机理的一般规律性以及其对蓝藻细胞作用的活性氧(ROS)破坏机制。TiO_2光催化技术未来的发展趋势具有长期可行性,但在实际应用中新型结构单元的高效光催化剂的探索,负载装置应用的完善以及对水体中有害毒素的去除仍然是研究的难题。     

Nano-Cu2O-loaded Paper: Green Preparation and High Visible Light Photocatalytic Performance for Formaldehyde Removal

The removal of formaldehyde (HCHO) from indoor air is of great importance to reduce health risks and improve indoor air quality. In this study, nano-Cu₂O-loaded paper with superior photocatalytic activity under visible light for the removal of HCHO was fabricated through a green, simple, and fast in situ synthesis method. The optimum preparation conditions for nano-Cu₂O-loaded paper were as follows: 2 g (oven-dry basis) cellulose fibers, CuSO₄ dosage 8 g, NaOH dosage 1.6 g, temperature 80℃, 60 min for Cu²⁺ absorption, and 60 min for reaction. Under the optimum conditions, the Cu₂O deposition ratio approached 30% and the nano-Cu₂O-loaded paper exhibited a catalytic efficiency of approximately 97% for HCHO removal. The photocatalytic capacity of nano-Cu₂O-loaded paper for HCHO removal had a positive correlation with the deposition ratio of nano Cu₂O particles. Excellent antibacterial property of nano-Cu₂O-loaded paper against Staphylococcus aureus and Escherichia coli was also confirmed. Moreover, nano-Cu₂O-loaded paper was proven to be hydrophobic.     

SnO2@TiO2核-壳纳米线的制备及其光催化性能研究

本文通过固-液-气(VLS)生长机制,利用化学气相沉积法(CVD)制备SnO₂纳米线。利用原子层沉积(ALD)以钛酸四异丙酯为前驱体在SnO₂纳米线表面沉积不同厚度的TiO₂壳层,形成SnO₂@TiO₂核-壳纳米线结构。通过中间Al₂O₃插层,分别制备出金红石和锐钛矿两种不同晶型的TiO₂,从而制备出两种不同复合结构的SnO₂@TiO₂核-壳纳米线。实验研究该复合结构中TiO₂的厚度与晶型对紫外光下光催化降解甲基橙溶液活性的影响。     

Bi7Ti4NbO21的合成、酸化及光催化性能

采用化学溶液分解法制备了Aurivillius结构钛酸铋铌化合物Bi₇Ti₄NbO₂₁,并对其进酸化处理。X射线衍射(X-ray diffraction, XRD)表征表明, 500 ℃以上的温度进行热处理,可以制得结晶性良好的Bi₇Ti₄NbO₂₁。 对Bi₇Ti₄NbO₂₁进行浓硝酸酸化处理,可转化为结晶性良好的焦绿石结构钛酸铋化合物Bi₂Ti₂O₇。采用SEM观察了所合成的Bi₇Ti₄NbO₂₁和Bi₂Ti₂O₇的形貌和尺寸。在紫外光照射下对甲基橙的光催化降解实验表明,所合成的钛酸铋铌化合物Bi₇Ti₄NbO₂₁及其酸化产物钛酸铋Bi₂Ti₂O₇均具有良好的光催化活性。试验结果表明,光催化剂颗粒的结晶性及其尺寸对其光催化活性均具有很大影响。550 ℃热处理得到的Bi₇Ti₄NbO₂₁具有最高的催化活性,而将钛酸铋铌酸化处理得到的Bi₂T_i2O₇其光催化性能显著提高,优于标准光催化剂P25。     

金属离子掺杂对离子液辅助制备纳米TiO_2性能的影响

以过渡金属(Cr、Fe、Ni和Zn)掺杂为手段,以溶胶凝胶为制备方法,以离子液2—羟基咪唑甲酸盐为微观结构调控试剂,制备了TiO_2纳米粒子。将样品备好后,在500℃的条件下进行煅烧处理,用BET、XRD、DRS等手段进行结构表征,以酸性蓝92为模拟污染物对其光催化性能进行测定。研究结果表明,经过渡金属掺杂后的TiO_2纳米颗粒比纯TiO_2具有更高的比表面积和更小的粒径尺寸。过渡金属的掺杂使TiO_2的吸收光谱向可见光的方向移动。在紫外灯照射下,水溶液中酸性蓝92的光降解结果为:过渡金属离子的存在使TiO_2纳米颗粒的光催化活性得到了明显增强。     

偏钒酸钾-硝酸铊纳米复合粉体的制备及其光催化降解苏丹红Ⅱ号的研究

采用硝酸铊、偏钒酸钾、亚硫酸钠、二氧化锰为反应原料,经过水热法合成出了偏钒酸钾-硝酸铊纳米复合粉体,活化该复合粉体后考察其对苏丹红Ⅱ号的降解能力,并对粉体进行SEM、XRD、XPS表征。实验结果表明,偏钒酸钾掺杂量为2.5%(质量分数)的复合粉体具有最强的催化活性,25 mg的偏钒酸钾-硝酸铊纳米复合粉体可对200 m L浓度为1×10~(-3)mol/L的苏丹红溶液有效降解。     

溶剂热制备ZnO微椭圆球及光催化性能

通过简便实用的溶剂热法制备出尺寸和形貌均一、单分散的纳米ZnO微椭圆球.用X-射线衍射仪、扫描电镜、氮气吸附和脱附仪和荧光光谱表征所合成的样品.通过控制实验条件来研究ZnO微椭圆球的形貌形成过程.除此之外我们还研究了ZnO微椭圆球光致发光和光催化性能.     

TiO_2-硅藻土复合光催化剂的制备及其对有机染料的降解

为探索用于染料废水处理的新型矿物材料光催化染料复合剂的合成和效果,采用硅藻土表面包覆TiO2,制备TiO2-硅藻土纳米复合光催化剂,研究不同TiO2包覆量、煅烧温度、干燥温度、催化剂用量因素对复合光催化剂降解次甲基蓝效果的影响。结果表明:复合光催化剂的最佳合成条件为:煅烧温度500℃,干燥温度70℃,TiO2包覆量为25%,复合光催化剂处理次甲基蓝用量1g/L。所制备纳米级TiO2-硅藻土纳米复合光催化剂对次甲基蓝的脱色率可达90%。     

Atmospheric pressure chemical vapour deposition and characterisation of crystalline InTaO4, InNbO4 and InVO4 coatings

The possibilities to grow crystalline complex InTaO₄, InNbO₄ and InVO₄ coatings as well as single oxide layers In₂O₃, Ta₂O₅, Nb₂O₅, and VO_x were investigated using aerosol assisted atmospheric pressure chemical vapour deposition technique. Indium(III) and niobium(IV) tetramethylheptanedionates, tantalum(V) tetraethoxyacethylacetonate and vanadium(III) acethylacetonate were used as precursors, monoglyme and toluene as solvents. The influence of deposition conditions and solution composition on elemental and phase compositions of layers was studied. Indium tantalate layers containing pure monoclinic InTaO₄ phase were obtained ex-situ, i.e., after high-temperature (800 °C) annealing of layers grown at lower temperature (500 °C). Films containing pure orthorhombic indium vanadate or monoclinic indium niobate phase may be prepared using both in-situ (600 °C) or ex-situ (deposition at 400 °C, annealing at 800 °C) approaches. Under optimised deposition conditions and solution compositions, Ni-doped InVO₄ and InTaO₄ films were also deposited and their photocatalytic activity was tested.