染料敏化太阳能电池用CuO-NRs/GNs复合对电极的研究

采用均匀沉淀法制得的氧化铜纳米棒(CuO-NRs)与石墨烯(GNs)浆料复合,利用电流体动力学技术(EHD技术)在FTO导电玻璃基片上制备CuO-NRs/GNs复合对电极。通过XRD物相分析,和SEM、TEM结构表征,表明CuO-NRs/GNs复合薄膜具有多孔的网络结构,通过一系列电化学性能测试,证明CuO-NRs/GNs复合对电极具有较高的电催化活性,和较快的电子传输速率,由CuO-NRs/GNs复合对电极组装的DSSC光电转换效率(2.57%)达到了与Pt对电极(3.46%)相当的水平。     

透明硫化钴对电极在染料敏化太阳能电池中的应用

硫化钴纳米材料是一种重点研究的染料敏化太阳能电池对电极材料。本工作以氟掺杂二氧化锡导电玻璃为基片, 采用反向恒压电沉积法制备透明硫化钴薄膜。实验结果表明: 电镀溶液的pH是硫化钴薄膜表面形貌形成的关键性因素, 而电沉积圈数可以有效控制硫化钴薄膜的厚度。电化学测试结果表明: 硫化钴薄膜对电极展现出了良好的电催化活性, 尤其是在电镀溶液pH为7.2、电沉积圈数为12圈的最佳条件下制备的硫化钴对电极具有大量的纳米薄片状结构, 有利于增加电催化活性位点, 使得其展现出了比铂电极更加优异的电催化性能。由此电极组装的染料敏化太阳能电池的能量转换效率达到7.26%, 10个电池器件的平均效率为7.18%, 高于相应铂电极器件的电池效率(6.94%)。     

黑枸杞与石墨烯纳米片在染料敏化太阳能电池中的应用

从高原黑枸杞中提取染料, 利用紫外-可见吸收光谱和循环伏安方法研究不同pH染料的光电化学性能, 确定染料最佳pH。以石墨烯为原料制备不同含量乙基纤维素(EC)的石墨烯纳米片(GNs)对电极, 用电化学阻抗、循环伏安、塔菲尔极化曲线研究不同EC含量对GNs对电极电催化性能的影响。以最佳pH染料为光敏剂, 不同含量EC的GNs为对电极组装染料敏化太阳能电池在模拟太阳光下测试光电转换效率。结果表明, EC含量为10wt%时, GNs对电极有良好的电催化性。光电测试EC含量为10wt%的GNs对电极光电转换效率为0.92%, 接近Pt对电极(0.99%)。     

染料敏化太阳能电池介孔石墨相C3N4对电极的制备及电催化性能研究

以氰胺为原料,通过硬模板法制备了介孔石墨相C_3N_4(mg-C_3N_4)。用mg-C_3N_4代替Pt制备染料敏化太阳能电池对电极,并对其电催化性能进行了研究。N2吸附数据表明所制备的mg-C_3N_4具有较高的比表面积(87.4m2/g)和较大孔体积(0.45cm3/g)。电化学阻抗谱分析表明所制备的mg-C_3N_4电极的电荷跃迁电阻为42.5Ω·cm2,证明mg-C_3N_4电极对I3-还原反应具有较高的电催化活性。以mg-C_3N_4电极作为对电极组装染料敏化太阳能电池,在100mW/cm2光照下(AM 1.5),电池的光电转换效率达到3.72%,比无孔石墨相C_3N_4对电极所组装染料敏化太阳能电池的光电转换效率提高了103%。     

合成介质对PEDOT催化染料敏化太阳电池光阴极性能的影响

采用聚3,4-乙烯二氧噻吩(PEDOT)/FTO为对电极,研究了合成介质对循环伏安法电聚合制备的PEDOT/FTO对电极性能的影响。通过SEM、CV、EIS、Tafel曲线,并首次采用SECM方法对所制备的对电极的电催化性能进行了表征。结果表明:在LiClO4水溶液和1-丁基-3-甲基四氟硼酸盐离子液体(IL)中制备的光阴极具有良好的电催化性能。J-V测试曲线表明,在LiClO4水溶液和IL中制备的光阴极所组装的DSSC器件的光电转化效率分别达6.4%和6.6%,接近于同等条件下以Pt对电极构建的DSSC器件的光电转化效率。     

石墨/TiO2共混碳薄膜对电极的电学与电化学性能研究

本文将石墨、TiO2纳米晶以及TiO2胶体共混,采用旋涂法制备了碳薄膜对电极,并用于组装染料敏化太阳能电池。采用场发射扫描电子显微镜观察薄膜的表面形貌,采用四探针电阻率测试仪、电化学交流阻抗图谱及太阳能电池综合测试仪对碳对电极的电学、电化学性质以及电池的光电性能分别进行测试;研究了薄膜厚度对碳对电极导电性能与电化学催化性能的影响。结果表明随着厚度增加,碳对电极的方块电阻和界面电荷传输电阻均变小,分别可达到26.6Ω.sp-1和11.8Ω.cm-2,而电池的填充因子及光电转换效率增大。当碳薄膜厚度为19.5μm时,光电转换效率可达到Pt对电极的70%。     

一步法热分解制备染料敏化太阳能电池Pt对电极

用旋涂热分解前驱H2PtCl6·6H2O溶液制备Pt/FTO对电极,研究了旋涂退火次数对Pt/FTO对电极的载铂量、透光率和组装的染料敏化太阳能电池光电性能的影响。结果表明,用5次旋涂退火的对电极组装的电池具有最佳的能量转换效率(6.78%),高于用传统的磁控溅射对电极组装的电池。基于在最佳光电性能情况下对电极的旋涂次数和载Pt量,进一步优化H2PtCl6?6H2O前驱液的浓度和使用体积。采用一步滴涂退火处理,得到了具有高透光性、低载Pt量和高的组装电池效率的Pt/FTO对电极。用此一步法制备的Pt/FTO对电极,组装成的电池能量转换效率达到6.92%。     

石墨烯支持Pt纳米粒子修饰电极的制备及电催化活性研究

采用一步电化学法制备了石墨烯支持Pt纳米粒子修饰电极(Nano-Pt/ERGO/GCE),利用交流阻抗研究了电极的性能以及该修饰电极的电催化活性。结果表明,采用循环伏安法制备石墨烯支持Pt纳米粒子,具有制备方法简单且纳米粒子粒径可控等优点。与单独的Pt纳米粒子修饰电极相比,Nano-Pt/ERGO/GCE电极表面Pt粒子分布更均匀,对甲醇的氧化具有极强的电催化活性。研究成果在甲醇燃料电池的研发中具有潜在的应用价值。     

高电催化活性染敏电池对电极CNT/TiO_(2-x)N_x材料的制备

以钛酸异丙酯为钛源,CNTs为载体,结合水热和高温NH_3处理技术成功制备了CNT/TiO_(2-x)N_x复合物,并研究了其作为染料敏化太阳能电池(DSSC)对电极材料的电催化性能。采用X射线衍射、扫描电镜、透射电镜、X射线光电子能谱和循环伏安等表征手段对CNT/TiO_(2-x)N_x复合物的形貌、结构和电化学性能进行表征。结果表明:直径30~50 nm的CNTs和直径为3~8 nm的TiO_(2-x)N_x纳米线相互交联形成了三维的网状结构,这一结构有利于增大复合物与电解液的接触面积。复合物融合了N掺杂Ti O2的高电催化活性和CNTs的高导电性的优势使得复合物的光电效率高达7.16%,与贵金属催化剂Pt相当,有望成为DSSC对电极材料理想替代材料之一。     

ZnO—TiO2染料敏化太阳能电池的制备和性能

采用低温水溶液法制备ZnO纳米花,将其与TiO2纳米颗粒以不同的质量比混合制备成复合浆料,采用刮涂法涂敷在掺氟的SnOz透明导电玻璃（FTO）上制备ZnO纳米花-TiO2纳米颗粒复合薄膜光阳极,与Pt对电极和电解质组装成染料敏化太阳能电池（DSSC）。通过光伏性能和电化学阻抗谱测试分析,研究ZnO纳米花与TiO2纳米颗...     

Facile construction of high-electrocatalytic bilayer counter electrode for efficient dye-sensitized solar cells

To improve the mechanical rigidity of the electrocatalyst and assure a higher number density of catalytic sites of the counter electrode in dye-sensitized solar cells (DSCs), we have extended widely applied titanium tetrachloride treatment to construct a rough scaffolding underlayer for the platinized counter electrode. Field-emission scanning electron microscopy and atomic force microscopy images clearly depicted the platinum nanoparticles with a diameter of ca. 10 nm homogeneously distributed on the scaffolding underlayer of the bilayer counter electrode and thus led to a characteristically high surface roughness. The electocatalytic activity of this novel bilayer counter electrode was measured and compared with the corresponding properties of conventional sputtered Pt electrode. Interestingly, electrochemical impedance spectroscopy and cyclic voltammetry measurements further demonstrated the notably larger electrochemical active surface area and thereby higher electrocatalytic activity of the bilayer counter electrode. Consequently, under standard 1 sun illumination (100 mW cm(-2), AM 1.5), device with this bilayer counter electrode achieved a considerably improved fill factor of 0.67 and overall energy conversion efficiency of 7.09%, which was apparently higher than that of 0.60 and 6.37% for sputterd Pt electrode. Therefore, this present method paves a facile and inexpensive way to prepare high-electrocatalytic bilayer counter electrode in DSCs.     

Preparation and characterization of poly(3,4-ethylenedioxythiophene)–poly(styrene sulfonate) composite thin films highly loaded with platinum nanoparticles

In this work, we propose a simple and efficient, low-temperature (∼120 °C) process to prepare transparent thin films of poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS) loaded with high concentration (up to 22.5 wt%) of platinum (Pt) nanoparticles. Firstly, an improved polyol method was modified to synthesize nano-sized (∼5 nm) and mono-dispersed Pt particles. These nanoparticles were incorporated into the matrix of PEDOT:PSS thin films via a spin coating/drying procedure. The electrochemical activities of the PEDOT:PSS thin film modified electrodes with respect to the I⁻/I₃⁻ redox reactions were investigated. It was found that the modified electrode of PEDOT:PSS thin film containing 22.5 wt% Pt exhibited the electrochemical activity comparable to the conventional Pt thin film electrode, suggesting that this electrode has good potential to serve as a counter electrode in dye-sensitized solar cells.     

Novel counter electrodes based on NiP-plated glass and Ti plate substrate for dye-sensitized solar cells

Novel counter electrodes based on NiP-plated glass and Ti plate substrate were prepared by thermal decomposition of H₂PtCl₆. Their properties and application in dye-sensitized solar cells were investigated. Platinized Ti plate electrode (Pt/TP electrode) and platinized NiP-plated glass electrode (Pt/NiP electrode) exhibited the same electrochemical activity for triiodide reduction as platinized fluorine-dope tin oxide (FTO) conducting glass electrode (Pt/FTO electrode). However, Pt/NiP electrode and Pt/TP electrode have the advantage over the Pt/FTO electrode in increasing the light reflectance and reducing the sheet resistance, which resulted to improve the light harvest efficiency and the fill factor of the dye-sensitized solar cells effectively. Examination of the anodic dissolution indicated the good stability of the Pt/NiP electrode and Pt/TP electrode in the electrolyte containing iodide/triiodide.     

Sub-micrometer-sized graphite as a conducting and catalytic counter electrode for dye-sensitized solar cells

Sub-micrometer-sized colloidal graphite (CG) was tested as a conducting electrode to replace transparent conducting oxide (TCO) electrodes and as a catalytic material to replace platinum (Pt) for I(3)(-) reduction in dye-sensitized solar cell (DSSC). CG paste was used to make a film via the doctor-blade process. The 9 μm thick CG film showed a lower resistivity (7 Ω/?) than the widely used fluorine-doped tin oxide TCO (8-15 Ω/?). The catalytic activity of this graphite film was measured and compared with the corresponding properties of Pt. Cyclic voltammetry and electrochemical impedance spectroscopy studies clearly showed a decrease in the charge transfer resistance with the increase in the thickness of the graphite layer from 3 to 9 μm. Under 1 sun illumination (100 mW cm(-2), AM 1.5), DSSCs with submicrometer-sized graphite as a catalyst on fluorine-doped tin oxide TCO showed an energy conversion efficiency greater than 6.0%, comparable to the conversion efficiency of Pt. DSSCs with a graphite counter electrode (CE) on TCO-free bare glass showed an energy conversion efficiency greater than 5.0%, which demonstrated that the graphite layer could be used both as a conducting layer and as a catalytic layer.     

电化学噪声技术检测核电环境材料的腐蚀损伤

探讨和解决了电化学噪声技术在核电环境材料腐蚀损伤检测应用的关键问题,建立了基于零阻电流(ZRA)检测的SCC电化学噪声测试体系.采用小面积的Pt或表面热喷涂陶瓷涂层的工作电极材料作为对电极,研制适用于核电现场检测的多种电化学传感器.运用Compact RIO模块化仪器和设计制作的基于ZRA电路的电化学噪声测试模块,实现电位-电流噪声的同步测量和采集.成功研制出便携式核电材料损伤检测系统.应用研制的测试系统和电化学传感器研究了高温高压和动态水环境304不锈钢的电化学噪声谱特征.并初步实现了在役核电站辅助车间不锈钢管道表面直接腐蚀检测和钢厂动力锅炉连续排污管的现场腐蚀检侧,取得了比较满意的结果.     

Electrochemistry and electrogenerated chemiluminescence with a single faradaic electrode

We describe an electrochemical cell containing a single faradic electrode (a Pt ultramicroelectrode) and a blocked (polarized) electrode (Si with an insulating SiO2 film) that served as a capacitive counter electrode. When a bias was applied between the two electrodes, a current was observed from a faradic process at Pt and a capacitive current at the blocking electrode. A steady charging current was obtained when the solution was moved along the insulator to continuously contact fresh surface (emersing a layer of charged ions and electronic countercharge into the gas phase). Electrogenerated chemiluminescence was clearly observed from a system containing Ru(bpy)(3)2+ in this kind of cell under pulsed excitiation, demonstrating that faradaic reactions can be carried out in an electrochemical cell without generation of any products at a counter electrode. The use of such a system for coulometric addition of desired species in nanosystems and in synthesis is suggested.     

Layer-by-layer self-assembled mesoporous PEDOT-PSS and carbon black hybrid films for platinum free dye-sensitized-solar-cell counter electrodes

A thin film of poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonic acid) (PEDOT-PSS), which is an alternative cathodic catalyst for Pt in dye-sensitized solar cells, was prepared using the layer-by-layer self-assembly method (LbL). The film is highly adhesive to the substrate and has a controllable thickness. Therefore, the PEDOT-PSS film prepared using LbL is expected have high performance and durability as a counter electrode. Moreover, when carbon black was added to the PEDOT-PSS solution, highly mesoporous PEDOT-PSS and carbon black hybrid films were obtained. These films showed high cathodic activity. In this study, we investigated the change in morphology in the obtained film with increasing carbon black content, and the influence of the porosity and thickness on the performance of the cells. In this study, a Pt-free counter electrode with performance similar to that of Pt-based counter electrodes was successfully fabricated. The achieved efficiency of 4.71% was only a factor of 8% lower than that of the cell using conventional thermally deposited Pt on fluorine-doped tin oxide glass counter electrodes.     

Multi-walled carbon nanotubes as a new counter electrode for dye-sensitized solar cells

Airbrushed multi-walled carbon nanotube (MWNT) networks were investigated as a new counter electrode for dye-sensitized TiO2 photoelectrochemical solar cells. The structural and physical properties of the MWNTs were studied by various techniques including SEM, TEM, Raman, optical absorption, and electrochemical impedance spectroscopy (EIS). The MWNTs exhibited catalytic activity for the reduction of triiodide in the electrolyte as studied by EIS measurements. The performance of the dye-sensitized solar cells was improved by using MWNTs as counter electrodes. This observation is explained by the significantly increased contact area between the MWNT counter electrode and the electrolyte which facilitates efficient charge transportation in the solar cell. We demonstrated that the MWNTs are suitable for replacing expensive Pt electrodes for fabricating high efficiency dye-sensitized solar cells. The process used in this study is also technically attractive for large scale and economic production.