人工神经网络优化碳钢表面TiO2修饰膜制备工艺

在改进常规制备方法的基础上,采用化学镀/溶胶-凝胶复合法在碳钢表面制备TiO2修饰膜,利用人工神经网络优化制备工艺,研究较优条件下制备的TiO2修饰膜在0.5mol/L硫酸溶液中的耐蚀性能。     

TiO2复合膜的耐蚀性能研究

采用化学镀／溶胶－凝胶复合法在碳钢表面制备TiO2复合膜，用X射线衍射法研究复合膜的组织形态，采用环境扫描电镜（ESEM）表征了复合膜的表观形貌，用极化阻力、电化学阻抗谱测量等方法研究了TiO2复合膜在0．5mol/L硫酸和0．5mol/L氯化钠溶液中的耐蚀性能。结果表明A3钢表面的TiO2复合膜耐蚀性能优良。     

Cu2O/TiO2/Pt复合薄膜的制备及其性能

为了降解环境污染物,通过磁控溅射的方法在玻璃基底上溅射沉积Cu2O/TiO2/Pt复合薄膜。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外可见分光光谱仪(UV-vis)和光致发光光谱仪(PL)对复合薄膜的表面形貌和光学性能进行分析。通过可见光下对甲基橙溶液的光催化降解试验研究了薄膜的光催化活性。结果表明:Cu2O/TiO2/Pt复合薄膜共有3层,从下到上依次为Pt层、锐钛矿型TiO2层和Cu2O层。薄膜表面平整致密,由形状规则的球形颗粒组成。Cu2O/TiO2/Pt复合薄膜的光催化活性高于Cu2O/TiO2复合薄膜的和纯TiO2薄膜的光催化活性。光催化活性的提高是由于Pt层的存在进一步抑制了光生电子与空穴的复合,延长了光生载流子的寿命,提高了量子产率,进而有效地改善了薄膜的光催化活性。     

Primary investigation of corrosion resistance of Ni-P/TiO2 composite film on sintered NdFeB permanent magnet

In this paper, an electroless nickel plating and sol-gel combined technique used to prepare the Ni-P/TiO₂ composite film on sintered NdFeB permanent magnet is described and the composite film was characterized by X-ray diffraction (XRD), environmental scanning electron microscopy (ESEM), and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO₂ film was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (i_corr) of Ni-P/TiO₂ composite film is 2.38μA/cm² in 0.5mol/L H₂SO₄ solution about 33% of that of Ni-P coating and 0.22μA/cm² in 0.5mol/L NaCl solution about 14% of that of Ni-P coating, respectively. In 0.5mol/L H₂SO₄ and 0.5mol/L NaCl solutions, the polarization resistance (Rp) of the composite film is 12.5kΩ cm² and 120kΩ cm², about 1.6 and 2 times that of Ni-P coating, respectively. The results indicate that Ni-P/TiO₂ composite film has a better corrosion resistance than Ni-P coating.     

浸镀铜前处理对铝合金表面Ni-P镀层结构与性能的影响

化学镀Ni-P是提高铝合金表面耐蚀耐磨性的主要方法之一,但施镀前通常要进行前处理,以去除表面氧化膜。以氯化胆碱-乙二醇低共熔体系为溶剂,CuCl2·2H2O为铜源,通过浸镀方法在铝合金表面制备铜层,再后续化学镀NiP,并与未经浸镀前处理和浸锌前处理铝合金表面的化学镀Ni-P层进行对比。利用扫描电子显微镜、X射线衍射、动电位极化及ASTM D3359-93胶带测试法研究了不同前处理方法对Ni-P镀层结构和性能的影响。结果表明:与未经浸镀前处理和浸锌前处理相比,通过浸镀铜前处理的铝合金表面得到的Ni-P镀层呈常规的胞状颗粒结构,腐蚀电位与腐蚀电流分别为-0.343V和2.109×10-6 A/cm2,耐蚀性较好;根据ASTM D3359-93标准,镀层与基底的附着性为5B。     

Preparation and photocatalytic activity of PANI/TiO2 composite film

1. Introduction As an advanced oxidation technique (AOT), photocatalytic oxidation of semiconductor nanopar-ticles has been widely investigated by several groups during the past two decades [1-2]. Among all types of oxide semiconductor photocatalysts, nano-TiO2 is a very important photocatalyst for its strong oxidiz-ing power, nontoxicity, and long-term photostability [3]. Some researchers have reviewed the photocata-lytic mechanism of nano-TiO2 [4-5]. Generally, when the surface of TiO2 i…     

聚苯胺/聚吡咯复合薄膜的制备及其抗腐蚀性能研究

采用循环伏安法在不锈钢表面电聚合聚苯胺/聚吡咯复合薄膜.利用动电位极化曲线法和电化学阻抗法研究了聚苯胺/聚吡咯复合薄膜的耐蚀性及其影响因素.结果表明:在3.5%NaCl溶液中,不锈钢表面覆盖复合膜以后,其自腐蚀电位比无膜和纯聚苯胺膜时提高,耐蚀性能增强,且复合膜的耐蚀性受电解液浓度、扫描次数、扫描速率及扫描上限等因素的影响.电解液中苯胺和吡咯的浓度比及硫酸浓度的高低,都会影响膜的致密度,从而影响膜的耐腐蚀性.电化学参数的改变会影响复合膜的聚合速率,使得复合膜的抗腐蚀能力不同.当苯胺和吡咯浓度比为7:3时,硫酸浓度为1.1 mol/L,扫描次数为25次,扫描速率为60 mV/s,扫描上限为1.2 V时,采用循环伏安法共聚合苯胺和吡咯,可形成沉积致密度高、耐蚀性好的复合膜.     

AZ31镁合金表面聚多巴胺/羟基磷灰石复合膜层的耐蚀性研究

通过两步湿化学沉淀法,在AZ31镁合金表面制备了聚多巴胺/羟基磷灰石复合涂层。使用扫描电子显微镜 (SEM),原子力显微镜 (AFM),X射线光电子能谱 (XPS),X射线衍射仪 (XRD) 及傅里叶红外仪 (FT-IR) 等表征了样品的形貌及结构。结果表明,聚多巴胺膜层平滑致密,经聚多巴胺诱导沉积的羟基磷灰石膜为交错排列的片状羟基磷灰石垂直阵列。利用电化学极化曲线和阻抗谱表征了聚多巴胺/羟基磷灰石复合膜的耐蚀性能,结果显示复合膜使AZ31镁合金在SBF溶液中的耐腐蚀性能明显提高。     

纳米CdTe/TiO2复合材料对304不锈钢的光生阴极保护行为

目的研究纳米CdTe/TiO_2复合材料对304不锈钢的光生阴极保护行为。方法采用阳极氧化法制备二氧化钛纳米管,通过循环伏安沉积法在纳米管上进行CdTe修饰。应用扫描电镜(SEM)、X射线衍射(XRD)等测试方法对比纯TiO_2与CdTe/TiO_2的表面形貌与晶相特征。结合开路电位(OCP)、光电流密度-时间曲线(J-t)、Tafel极化曲线等电化学方法,研究复合材料的光电转化性能及其对304不锈钢的阴极保护行为。结果在光照条件下,耦连CdTe/TiO_2复合材料的304不锈钢的开路电位从初始的-190mV负移至-730mV,光电流密度可达0.15mA/cm~2,闭光后,开路电位上升至-350mV,仍然具有保护作用,说明制备的纳米CdTe/TiO_2复合材料具有储存电子的能力。结论在可见光照射下,与纯二氧化钛相比,制备的CdTe/TiO_2复合材料对304不锈钢的阴极保护性能显著提高,且在闭光状态下仍能维持对不锈钢的保护,对不锈钢起到一定的延时保护效果。     

TiO2 / 玻璃鳞片复合颗粒的制备及抗渗透性能研究

目的制备TiO2/玻璃鳞片复合颗粒以改善玻璃鳞片与涂层的界面性能,提高复合涂层的抗渗透能力。方法利用溶胶回流法在玻璃鳞片表面制备一层TiO2薄膜,通过SEM,EDS以及XPS等技术表征TiO2薄膜的表面状态。制备复合涂层,利用EIS和盐雾试验测试TiO2/玻璃鳞片的抗渗透能力,并与玻璃鳞片的抗渗透性进行对比。结果玻璃鳞片表面被TiO2薄膜包覆,TiO2薄膜与玻璃鳞片表面以Si—O—Ti化学键连接,浸泡15 d后,玻璃鳞片涂层的Zw为8781Ω,TiO2/玻璃鳞片涂层的Zw为75234Ω。盐雾试验后,TiO2/玻璃鳞片涂层下的金属几乎没有腐蚀。结论玻璃鳞片经过TiO2包覆后,具有较强的抗渗透能力。     

Formation and capacitance properties of Ti-Al composite oxide film on aluminum

Al specimens were covered with TiO2 film by sol-gel dip-coating and then anodized in ammonium adipate solution. The structure, composition and capacitance properties of the anodic oxide film were investigated by transmission electron microscopy (TEM), Auger electron spectroscopy (AES), X-ray diffractometry (XRD) and electrochemical impedance spectroscopy (EIS). It was found that an anodic oxide film with a dual-layer structure formed between TiO2 coating and Al substrate. The film consisted of an inner Al2O3 layer and an outer Ti-Al composite oxide layer. The thickness of layers varied with the number of times of sol-gel dip-coating. The capacitance of anodic oxide films formed on coated specimens was at most 80% higher than that without TiO2. In film formation mechanism, it was claimed that the formation of composite oxide film was mainly affected by the structure of micro-pores network in TiO2 coating which had an influence on Al3+ and O2- ions transport during the anodizing.     

Ni-P-ZrO2化学复合镀层对TC4钛合金抗氧化性能和阻燃性能的影响

在TC4钛合金微弧氧化膜表面制备Ni-P-ZrO2化学复合镀层,研究其在600和700℃空气中的抗高温氧化性能,利用脉冲激光烧蚀处理研究其阻燃性能。结果表明,Ni-P-ZrO2化学复合镀层在600和700℃空气中的氧化动力学曲线呈抛物线形状,氧化膜薄且致密,主要以NiO为主,镀层中非晶的NiP相转变成晶态的Ni2P相,具有良好的抗氧化性能。激光烧蚀处理时,Ni-P-ZrO2镀层烧蚀体积、面积分别是TC4烧蚀的1/3和1/2。镀层激光烧蚀处理后,在烧蚀孔洞内部出现柱状晶粒,ZrO2粒子在镀层表面发生团聚,Ni-P-ZrO2化学复合镀层能有效地提高钛合金的阻燃性能。     

靶电流对磁控溅射AlSn20/C镀层耐蚀性的影响

采用非平衡磁控溅射技术在铝基轴承合金表面制备AlSn20/C复合镀层,通过扫描电镜形貌观察、交流阻抗和极化曲线的测量研究石墨靶电流对镀层组织与耐蚀性能的影响。结果表明:在电流0.2~0.8 A范围内,薄膜均以层状结构生长,且电流越小,薄膜组织越致密;镀膜后试样的电化学阻抗比基体的高5~6个数量级,石墨靶电流为0.2 A时,可将基体的自腐蚀电位由1.42 V提高到1.18 V,石墨靶电流是影响AlSn20/C复合镀层耐蚀性的一个重要因素,石墨靶电流越小,其耐蚀性越好。     

Ti/nano-TiO2-Pt复合电极催化甲醇氧化的研究

采用溶胶-凝胶法(sol-gel)制备纳米TiO2(Ti/nano-TiO2)膜电极,再用电沉积法在纳米TiO2膜上修饰Pt微粒,制成Ti/nano-TiO2-Pt复合电极.用循环伏安法研究了纯Pt丝电极和Ti/nano-TiO2-Pt电极对甲醇氧化的电催化活性以及稳定性.结果表明:对甲醇氧化,复合电极比Pt丝电极具有更高的催化活性,且对甲醇氧化中间产物CO的吸附量少,因而不易中毒;复合电极载铂量达到一定值时,电极具有最强的催化活性.     

银表面聚苯胺/聚吡咯复合膜的制备及其耐蚀性

以三氯化铁为氧化剂,苯胺、吡咯为基体,采用化学氧化法在银片表面制备了聚苯胺/聚吡咯(Pani/Ppy)复合膜。采用红外光谱(IR)、热重分析(TG)、扫描电子显微镜(SEM)、电化学极化分析、自腐蚀电位-时间分析等研究了复合膜的表面形貌、热力学稳定性及耐蚀性。结果表明:n(Ani)/n(Py)为1/3的复合膜的热分解温度为450℃,能在其工作温度范围内(20~300℃)满足使用要求;复合膜对银片具有明显的防腐蚀效果,其中n(Ani)/n(Py)为1/3的复合膜的防腐蚀效果最佳。     

ZrO_2／TiO_2复合光催化膜的微弧氧化法制备及表征

采用微弧氧化方法和原位生成的Zr（OH）_4胶体颗粒,在纯钛基体上制备ZrO_2／TiO_2复合光催化膜。采用SEM、EDX、XRD、UV-VisDRS等分析手段,对膜层进行分析表征。结果表明：复合膜显示出层状和多孔的结构,由锐钛矿、金红石和ZrO_2组成;相对于纯TiO_2膜,复合膜层的光吸收截止边缘产生红移;ZnO_2／TiO_2复合膜层和纯TiO_2膜层在紫外光照射下,对罗丹明B的光催化速率常数分别为0．0442和0．0186h~（-1）。     

Preparation and electrocatalytic property of Au-Pt/SnO2/GC composite electrode

Au-Pt/SnO2/GC composite electrode was prepared by self-assembling Au-Pt nanoparticles on SnO2 film, which was deposited on actived glassy carbon (GC). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) images revealed that dense and uniform Au-Pt particles with 25-nm diameter were dispersed on SnO2 film. X-ray photoelectron spectroscopy (XPS) results proved that there was an interaction between Au-Pt nanoparticles and SnO2 support. Electrochemical experiments showed that Au-Pt/SnO2/GC composite electrode had a good electrocatalytic activity to the oxidation of methanol.     

Preparation and characterization of the TiO2-V2O5 photocatalyst with visible-light activity

Visible-light responsive TiO2-V2O5 catalyst was prepared using a binary sol-gel and in-situ intercalation method. The TiO2 sol and V2O5 sol were mixed to disperse the V2O5 species in the TiO2 phase at molecular level. The binary sol was then intercalated into interspaces of polyaniline （PANI） by means of in-situ polymerization of aniline. Conglomeration of the TiO2-V2O5 dusters during the calcination process was avoided because of the wrap of polyaniline. The surface mor- phology, the crystal phases, the structure, and the absorption spectra of （PANI）,/TiO2-V2O5 and the composite catalyst were studied using SEM, XRD, FT-IR, and UV-Vis. The photoactivity of the prepared catalyst under UV and visible light irradiation were evaluated by decolorization of methylene blue （MB） solution. The results showed that the composite catalyst displayed a homogeneous anatase phase, and the vanadium pentoxide species was highly dispersed in the TiO2 phase. The composite catalyst responded to visible light because of the narrowed band gap. In this study, the catalyst with the sol volume ratio of TiO2： V2O5 = 10：1 presented the best photocatalytic activity.     

Ni—P镀层磷含量对Ni—P／TiO2复合膜耐蚀性能的影响

采用化学镀／溶胶一凝胶技术在碳钢表面制备了低磷（Ni—LP／TiO2）、中磷（Ni-MP／TiO2）和高磷（Ni-HP／TiO2）Ni—P／TiO2复合膜．采用X衍射分析仪和环境扫描电镜表征了Ni—P／TiO2复合膜的结构与形态．应用动电位极化和极化阻力（Rp）测量研究了复合膜在0．5mol／l,H2SO4溶液中的耐蚀性能。实验结果表明Ni—P／TiO2复合膜耐蚀性能优于Ni-P镀层,随NiP镀层磷含量的增加,Ni—P／TiO2复合膜的耐蚀性增强。Ni—HP／TiO2复合膜在0．5mol/L H2SO4溶液的自腐蚀电流密度（icorr）为3．15μA·cm^-2,分别为Ni—LP／TiO2和NiMP／TiO2复合膜的40％和62％;其Rp为11．72kΩ·cm^2．分别为Ni—LP／TiO2和Ni—MP／TiO2复合膜的1．5倍和1．3倍,Ni—HP／TiO2复合膜较NiLP／TiO2和Ni—MP／TiO2复合膜有更佳的耐蚀性能。     

Grain Size and Wettability of TiO2/SiO2 Photocatalytic Composite Thin Films

The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), BET surface area, FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the addition of SiO2 to TiO2 thin films can suppress the grain growth of TiO2 crystal, increase the hydroxyl content on the surface of TiO2 films, lower the contact angle for water on TiO2 films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0-° are obtained by the addition of 10%-20% SiO2 in mole fraction.