多硫电解质对CdS薄膜电池光电性能影响研究

在CdS薄膜的光电化学电池中,多硫电解质起着促进电子传递,减少电子空穴复合几率,从而提高电池光电转换效率的作用;但多硫电解质又会阻碍CdS薄膜对光的吸收。本文通过对CdS纳米管薄膜电池在含硫量不同的电解质中光电性能的考察,证明了0.5 mol/L Na2S、0.5 mol/L NaOH和0.5 mol/L S的液态电解质成分组合为本实验中制得的CdS纳米管薄膜光电化学电池的最佳电解质。     

P3HT修饰一维有序壳核式CdS/ZnO纳米棒阵列复合膜的光电化学性能

采用电化学方法在铟锡氧化物(ITO)导电玻璃上制备了高度有序的ZnO纳米棒阵列, 在ZnO纳米棒阵列上先后电化学沉积CdS纳米晶膜及聚3-己基噻吩(P3HT)薄膜得到P3HT修饰的一维有序壳核式CdS/ZnO纳米阵列结构, 并通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、能量散射X射线(EDX)等表征手段证实了该结构的形成. 以此纳米结构薄膜为光阳极组装新型半导体敏化太阳电池, 研究了CdS纳米晶膜的厚度和P3HT薄膜的沉积对电池光伏性能的影响, 初步探讨了电荷在电池结构中的传输机理, 结果表明, CdS纳米晶膜和P3HT薄膜的沉积有效地拓宽了光阳极的光吸收范围, 实验中电池的光电转换效率最高达到1.08%.     

电解液对CdS薄膜光电化学电池性能的影响

在光电化学电池中,电解液担负着传递电子的重要责任,因此选择一个最优的电解液对于电池整体效率的提高非常重要.本文通过对CdS薄膜的光电化学电池在六种不同的电解液体系中光电性能的考察发现,加入少量的KCl多硫电解液体系中可以稳定CdS薄膜,减少电子和空穴的复合几率,增加电子的传递速度,从而提高CdS薄膜光电化学电池的光电转...     

有机-无机半导体复合体系中光诱导电子转移及光电转换性质的研究

由于纳米材料技术和有机-无机复合材料技术的引入,染料敏化纳晶TiO₂薄膜光电化学太阳能电池以较高的能量转换效率,并以低价,清洁,稳定性好,性能优异等特点而成为一种大有应用前景的新型太阳能电池.其中,光诱导电子转移、能量传递是发挥其光电转换功能的关键过程.本论文围绕反胶束中纳米CdS的制备和表征及界面电荷转移、联吡啶钌的光物理性质和光电转换性质等进行了研究,得到的结论如下.     

硅基多孔氧化铝模板非水电沉积CdS纳米线的研究

纳米材料,包括尺寸为纳米量级的超细微粒?线?薄膜?量子阱和超晶格等引起了人们广泛的重视 [1,2] ?其中 , 半导体纳米微粒和由其构成的纳米固体结构开辟了材料科学研究的新领域?硫化镉 (CdS) 作为一种重要的Ⅱ - Ⅵ族无机半导体材料 , 具有独特的光电性质 , 在光电化学电池和多相光催化反应中都有广泛应用?近年来 , 已有大量关于合成 CdS 纳米结构的文献报导 [3～12] , 所采用的方法如反胶束法?单分子膜法?自组装法以及电化学沉积法等 , 其中非水电解与模板技术相结合的制备方法引起了人们高度的重视并且被广泛的采用?自从 Baranski 等在上…     

CdTe/CdS共敏化TiO2电极材料的制备与光电性能

将电沉积法和化学浴沉积法结合,分别将CdTe和CdS量子点纳米晶材料引入到TiO_2纳米管阵列上制备CdTe/CdS量子点共敏化TiO_2光电极。利用扫描电镜、X射线衍射和X射线能量色散光谱等测试手段对所得样品的形貌、晶型和组分进行表征。在模拟太阳光照射条件下,通过电化学工作站测试其光电化学性能。研究结果表明,相对于单一量子点敏化CdS/TiO_2和CdTe/TiO_2光电极而言,共敏化CdTe/CdS/TiO_2光电极表现出更好的光电转化性能,短路电流密度和光电转换效率分别可以达到3.1 m A·cm~(-2)和1.85%。此外,采用电化学阻抗测试技术对材料性能提升的原因进行深入的探究。     

多晶Hg0.09Cd0.91Te薄膜的光电化学行为

富镉Hg_(1-x)Cd_xTe是一种新型的光电转换材料,已用于固体结太阳能光伏电池:ITO/CdS/Hg_(1-)Cd_xTe/Au。我们曾对Hg_(1-x)Cd_xTe的电沉积机理作过研究。最近我们用电沉积制备的Hg_(0.09)Cd_(0.91)Te多晶薄膜做成了液体结太阳能光电化学电池并观察到明显光电响应。     

TiO2包覆不同微结构纳米碳纤维薄膜电极的光电化学性能

采用溶胶-凝胶法制备了TiO2包覆不同微结构的纳米碳纤维(Carbon nanofibers, CNF), 包括板式纳米碳纤维(Platelet-CNF, PCNF)和鱼骨式纳米碳纤维(Fish-bone-CNF, FCNF)的复合薄膜电极. 用光电流作用谱和光电流-电势图等方法研究了复合薄膜电极的光电化学性能. 研究结果表明, 复合薄膜电极表现出n型半导体特征, 薄膜中CNF的存在有助于光生电子和空穴有效地分离, 提高了光电转换效率, TiO2包覆PCNF薄膜电极在可见光范围内存在明显的光电响应.     

拉氏变换阻抗分析测量CdSe薄膜电极的表面态

在光电化学光能转换的研究中,由于多种因素在半导体/溶液界面形成了各种性质和作用不同的表面态,在界面的电荷和能量转移中起着重要作用,对光电转换性能产生较大的影响。对于多晶半导体——作为具有实用前景和目前深受重视的光电转换材料,由于存在较多的晶格缺陷和晶粒界面,在表面形成了浓度较高的表面态,这些表面态可作为光生电子空穴的复合中心,是造成多晶材料光电转换效率低于单晶材料的主要原因。因此测量和研究半导体/溶液界面的表面态能量分布,性质及作用对研究光电转换过程的机理,特别是对改善多晶半导体的性能都具有直接的重要意义。     

光电催化分解水Ⅲ-Ⅴ族半导体光电极薄膜保护策略

Ⅲ-Ⅴ族半导体材料(如GaAs、InP、GaP等)具有抗辐射性能高、温度特性好、耐高温等特点。相比于其他材料构建的光电催化体系,由这类半导体构成的光电极具有更高的太阳能吸收效率和光电转换效率。然而,大多数Ⅲ-Ⅴ族半导体在水溶液电解质中的物理化学性质很不稳定,导致太阳能驱动分解水性能衰减较快。基于此,本文综述了薄膜保护层在改善Ⅲ-Ⅴ族半导体光电极电化学稳定性方面的主要成就和研究现状,分析总结了获得稳定高效的光电反应界面和分解水效率的策略,探讨了导致材料衰减的原因和相应改善措施,最后展望了薄膜保护策略的未来发展前景。     

The influence of DMSO on the formation and photoelectrochemical properties of CdS thin films by electrodeposition method

The homodispersed CdS nanoparticles were prepared on Sn-doped indium oxide substrates (ITO) to form smooth and uniform CdS thin films by electrodeposition method from a dimethyl sulfoxide (DMSO) solution containing cadmium chloride and sulfur. The structure and morphologies of samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The results indicate that DMSO played an important role in formation of CdS nanofilms by affecting the nucleation and growth of the CdS nanoparticles. So, a DMSO-assisted growth process was proposed as a plausible mechanism for the formation of smooth and uniform CdS nanofilms. According to the photoelectrochemical test, the CdS thin film prepared in 30 % DMSO + 70 % H₂O system exhibited maximum photocurrent and open circuit potentials. This is because the deposited CdS nanoparticles had better dispersity on ITO, which facilitated the propagation and kinetic separation of photogenerated charges.     

CdS和CdSe薄膜的制备及其光电化学性质

本文采用简易的化学水浴沉积法和自牺牲模板法制备CdS、CdSe薄膜,对两种薄膜进行了XRD表征,比较了两种薄膜的紫外吸收光谱并研究了CdS、CdSe薄膜作为太阳能电池中的光阳极时所产生的光电流和光电压,对两种薄膜的电化学性能进行了比较.     

Triton-X mediated interconnected nanowalls network of cadmium sulfide thin films via chemical bath deposition and their photoelectrochemical performance

Thin films of cadmium sulfide (CdS) have been wet chemically deposited onto fluorine-doped tin oxide (FTO) coated conducting glass substrates by using non-ionic surfactant; Triton-X 100. An aqueous solution contains cadmium sulphate as a cadmium and thiourea as sulphur precursor. Ammonia used as a complexing agent. The results of measurements of the x-ray diffraction, Raman spectroscopy, optical spectroscopy, energy dispersive spectroscopy, scanning electron microscopy, Brunauer Emmett Teller (BET) surface areas and atomic force microscopy were used for the characterization of the films. These results revealed that the films are polycrystalline, consisting of CdS cubic phase. The films show a direct band gap with energy 2.39 eV. The films show interconnected nanowalls like morphology with well-defined surface area. Finally, the photoelectrochemical (PEC) performance of Triton-X mediated CdS thin film samples were studied. The sample shows photoelectrochemical (PEC) performance with maximum short circuit current density (J_sc) 1.71 mA/cm² for larger area (1 cm²) solar cells.     

Photosensitization of TiO2 nanoparticulate thin film electrodes by CdS nanoparticles

Surface photovoltage spectra (SPS) measurements of TiO₂ show that a large surface state density is present on the TiO₂ nanoparticles and these surface states can be efficiently decreased by sensitization using CdS nanoparticles as well as by suitable heat treatment. The photoelectrochemical behavior of the bare TiO₂ thin film indicates that the mechanism of photoelectron transport is controlled by the trapping/detrapping properties of surface states within the thin films. The slow photocurrent response upon the illumination can be explained by the trap saturation effect. For a TiO₂ nanoparticulate thin film sensitized using CdS nanoparticles, the slow photocurrent response disappears and the steady-state photocurrent increases drastically, which suggests that photosensitization can decrease the effect of surface states on photocurrent response. Electronic Publication     

Sensitization of Mn with CdS nanoparticles via electrochemical deposition technique for photocurrent enhancement of nanomaterial’s-sensitized photoelectrochemical cells

A photoconversion efficiency of 2.12% was obtained under visible light illumination by nanostructure-sensitized photoelectrochemical cells using Mn/CdS as sensitizer loaded on TiO₂ nanotube arrays (NTAs) (Mn/CdS/TiO₂). Sensitization of Mn on CdS nanoparticles pre-loaded on TiO₂ NTAs was carried out by a two-step electrodeposition method. Compared with unsensitized TiO₂ NTAs, the photocurrent had increased from 0.03 to 4.12 for Mn/CdS/TiO₂ prepared at 1 min. The effects of deposited Mn on the physical, chemical, and photoelectrochemical properties of the CdS/TiO₂ NTAs nanostructure were investigated by using UV–visible diffuse reflectance spectroscopy, X-ray diffractometry, and field-emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. The photoelectrochemical analysis was examined in a three-electrode system under a halogen illumination by using the prepared film as the photo-anode.     

TiO2-MoO3复合纳米管阵列薄膜的制备及其可见光活性

通过阳极氧化的方法制备TiO₂纳米管薄膜, 在MoO₃存在的条件下对该薄膜进行热处理得到TiO₂-MoO₃复合纳米管阵列薄膜. 利用X射线衍射(XRD), 扫描电子显微镜(SEM), X射线光电子能谱(XPS), 电化学阻抗谱(EIS), Mott-Schottky 及光电化学方法对得到的薄膜进行了表征. XRD结果表明, TiO₂-MoO₃复合纳米管薄膜中的TiO₂主要为锐钛矿晶型. SEM实验证实了薄膜纳米管结构的存在, 样品中的MoO₃均匀地分散在TiO₂纳米管表面. 利用XPS方法分析了TiO₂-MoO₃复合纳米管薄膜元素的组成, 结果表明, MoO₃在TiO₂表面形成TiO₂-MoO₃复合纳米管薄膜. 研究了热处理温度以及热处理时间对样品的光电化学性能的影响, 相对于单纯TiO₂纳米管薄膜, 适量引入MoO₃提高了样品在可见光区的光电响应能力, 样品的平带电位负移. 在450 °C热处理60 min制得的TiO₂-MoO₃复合半导体纳米管阵列薄膜光电响应活性最高.     

In‐Situ Growth and Immobilization of CdS Nanoparticles onto Functionalized MoS2: Preparation,Characterization and Fabrication of Photoelectrochemical Cells

A facile strategy for the controllable growth of CdS nanoparticles at the periphery of MoS₂ en route the preparation of electron donor‐acceptor nanoensembles is developed. Precisely, the carboxylic group of α‐lipoic acid, as addend of the modified MoS₂ obtained upon 1,2‐dithiolane functionalization, was employed as anchor site for the in situ preparation and immobilization of the CdS nanoparticles in an one‐pot two‐step process. The newly prepared MoS₂/CdS hybrid material was characterized by complementary spectroscopic, thermal and microscopy imaging means. Absorption spectroscopy was employed to register the formation of MoS₂/CdS, by observing a broad shoulder centered at 420 nm due to CdS nanoparticles, while the excitonic bands of MoS₂ were also evident. Moreover, based on the efficient quenching of the characteristic fluorescence emission of CdS at 725 nm by the presence of MoS₂, strong electronic interactions at the excited state between the two species within the ensemble were identified. Photoelectrochemical assays of MoS₂/CdS thin‐film electrodes revealed a prompt, steady and reproducible anodic photoresponse during repeated on‐off cycles of illumination. A significant zero‐current photopotential of ?540 mV and an anodic photocurrent of 1 μA were observed, underlining improved charge‐separation and electron transport from CdS to MoS₂. The superior performance of the charge‐transfer processes in MoS₂/CdS is of direct interest for the fabrication of photoelectrochemical and optoelectronic devices.     

超声搅拌化学浴沉积法制备大颗粒和致密的CdS薄膜

采用超声搅拌化学浴法(UCBD)在SnO2:F透明导电玻璃衬底上制备了CdS薄膜.研究了退火和CdCl2处理对UCBD-CdS薄膜的表面形貌、晶体结构和直接带隙的影响,比较了沉积时间对UCBD-CdS薄膜中CdS聚集体颗粒大小和堆积致密性的影响.结果表明,CdCl2处理可使CdS聚集体中的小颗粒重新熔合在一起,但CdS聚集体的大小并没有改变.在UCBD-CdS薄膜的沉积过程中,CdS薄膜的横向和纵向生长速率之比会随着沉积时间的不同而改变,且沉积时间是获得大颗粒的CdS聚集体和致密的UCBD-CdS薄膜的重要影响因素.当沉积时间为40min时,获得的UCBD-CdS薄膜较致密,CdS聚集体的大小为180nm,膜厚为80.8nm,适合作为薄膜太阳电池的窗口层.     

Ion-exchange synthesis and improved photovoltaic performance of CdS/Ag2S heterostructures for inorganic-organic hybrid solar cells

A facile ultrasound-assisted ion exchange route was developed for the synthesis of CdS/Ag₂S heterojunctions by ion exchange between the nanostructured CdS film and [Ag(NH₃)₂]⁺ under ultrasonication. The CdS/Ag₂S heterojunction film was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis DRS spectroscopy, photoelectrochemical measurements, and the transient photovoltage (TPV) technique. CdSAg₂S heterojunctions exhibit a dense morphology, enhanced visible light absorption and stronger photocurrent response than the pure CdS films. Poly(3-hexylthiophene) (P3HT) was then spin coated into the CdS/Ag₂S framework. Hybrid solar cells constructed with FTO/CdS/Ag₂S/P3HT/Au display relatively higher power conversion efficiency than FTO/CdS/P3HT/Au.     

电沉积法制备介孔TiO_2/CdS薄膜光电极

采用阴极恒电位沉积法,在介孔TiO2薄膜上制备了介孔TiO2/CdS薄膜光电极,用XRD,SEM,Raman,SPS和UV-Vis等多种手段对薄膜电极进行了表征.结果表明,CdS成功沉积到介孔TiO2的表面和孔道内,形成了异质结结构.通过光电流作用谱考察了该复合体薄膜电极的光电性能,结果表明,与单纯的介孔TiO2薄膜相比,其光电转换效率显著提高,这是由于CdS具有吸收可见光的特性以及CdS与介孔TiO2形成异质结从而使得光生载流子更容易分离的结果.