X射线光电子能谱仪的数据采集及处理技巧

X射线光电子能谱(XPS)广泛应用于材料表面分析表征.在XPS分析过程中,对于经验不足的科研或者测试人员可能会引入一些主观性的判断,使得谱图测试及分析对数据分析质量产生影响.为获得更好的数据质量,本文根据国际标准和实际测试经验总结出一种通用于不同类型材料表面分析表征的XPS数据采集和处理分析思路,以方便测试人员能够更加...     

X射线光电子能谱复杂谱图的非线性最小二乘法分析案例

X射线光电子能谱(XPS)是材料表面分析表征最常用的测试手段之一,然而由于XPS数据处理过程中往往会带入主观因素,其数据分析往往是一个难题.本文重点报道了 XPS复杂数据分析的处理方法和案例,首先总结了非线性最小二乘法(NLLSF)分析XPS复杂谱图的适用范围;随后根据谱峰重叠的类型对实际测试分析过程中遇到的复杂数据进...     

正负压一体式无空气X射线光电子能谱原位转移仓的开发及研制

针对空气敏感材料的表面分析,为了获得更加真实的表面组成与结构信息,需要提供一个可以保护样品从制备完成到分析表征过程中不接触大气环境的装置.通过使用O圈密封和单向密封柱,提出一种简便且有效的设计概念,自主研制了正负压一体式无空气X射线光电子能谱(XPS)原位转移仓,用于空气敏感材料的XPS测试,利用单向密封柱实现不同工作需求下正负压两种模式的任意切换.通过对空气敏感的金属Li片和CuCl粉末进行XPS分析表明,采用XPS原位转移仓正压和负压模式均可有效避免样品表面接触空气,保证测试结果准确可靠,而且采用正压密封方式转移样品可以提供更长的密封时效性.研制的原位转移仓具有设计小巧、操作简便、成本低、密封效果好的特点,适合给有需求的用户开放使用.     

疏水性聚丙烯酸酯人工晶状体的低温等离子体改性

通过低温等离子体表面改性技术对疏水性聚丙烯酸酯人工晶状体进行表面改性, 并对改性前后材料的表面结构、形貌和光学性能进行了表征. 静态水接触角结果显示, 经过氨等离子体处理后的人工晶状体亲水性效果最好, 同时最佳的改性时间为120 s, 改性功率为150 W. XPS分析结果进一步证实, 经等离子体处理后, 在人工晶状体表面引入了极性基团. 原子显微镜观察结果显示, 改性后材料表面更加凹凸不平, 粗糙度显著增加而透光率变化很小, 但过大功率改性的样品透光率明显下降. 时效性测试结果表明, 人工晶状体在改性14 d后疏水性恢复趋于稳定.     

X射线光电子能谱在新型催化材料表征中的应用

X射线光电子能谱(XPS)在分析、表征材料尤其是表面组分分析方面有着极大的优势。综述了近5年来XPS在表征及测定新型光催化材料、新型分子筛催化材料、新型电催化材料、新型金属催化材料、新型金属氧化物催化材料以及其他新型催化材料的表面元素组成、原子价态及元素比率等方面的应用,概述了XPS分析测试过程中对环境的真空度要求,以及氧化对样品检测结果的干扰和影响,并就其应用前景提出了展望。     

XPS光电子峰和俄歇电子峰峰位表

在长期从事XPS分析测试的经验基础上,搜集了有关文献中的大量数据,编制了XPS光电子峰和俄歇电子蜂峰位表,用于正确识别各种样品XPS谱图中的电子峰,达到快速、正确分析各种样品元素组成和化学组成的目的.本峰位表对于从事XPS测试的分析人员和应用XPS的科技人员具有很好的实用价值.     

新型碳材料表面元素及化学态高分辨XPS定量研究*

X射线光电子能谱(XPS)在科学研究中被广泛应用于碳材料表面官能团识别和结构缺陷判定,对表面组成结构识别和性能调控具有重要指导意义。XPS数据分析主观性强、sp²杂化态对应C1s谱峰峰形不对称以及各化学态对应峰位差异相对较小等因素是导致碳材料XPS数据分析难度高的主要原因。本文通过对XPS分析碳材料现状总结了当前新型碳材料XPS数据分析方法的不足(主要包括■化学态对应C1s谱峰峰形不对称峰形、各化学态半峰宽拟合的随意化以及数据的主观化);并结合实际材料通过■化学态谱峰峰形参考化、半峰宽相对限定化以及多数据分析客观化对新型碳材料XPS数据方法进行进一步规范,为XPS应用于新型碳材料表面元素及化学态定量高分辨研究提供理论依据和技术保障。     

X射线光电子能谱仪的开放使用与管理

X射线光电子能谱仪(XPS)是材料表面元素定性和半定量分析的重要手段之一,是表面分析科研工作的必备仪器.为提高测试效率,实施了大型仪器设备开放共享优化,总结了在推动XPS开放过程中管理的经验和体会.     

氧化石墨烯-富里酸复合光催化剂的制备与分析

以氧化石墨烯作为载体,通过一种方便的自组装方法将富里酸分子固定在氧化石墨烯上,合成新型复合光催化材料GO-FA,并通过SEM、XRD、XPS等一系列的分析手段对其进行表征测试.同时,以尼泊金甲酯模拟废水,结合自由基捕获试验对降解机理进行探讨并进行对不同降解影响因素进行探究.表征结果显示富里酸颗粒包裹在氧化石墨烯表面,表...     

铁氰化镨修饰的电化学传感器的研制及其对半胱氨酸的测定

采用循环伏安法在PrCl3+K3Fe(CN)6溶液中于石墨电极表面电沉积铁氰化镨(PrHCF)薄膜,制备PrHCF修饰电极。对该修饰电极电化学的行为进行分析,包括扫描速度、K+浓度以及阴、阳离子对膜电极的影响。同时,以红外和XPS对膜进行了表征,IR谱图中氰基的伸缩振动峰证明了膜的存在;而XPS谱图中Fe2p1/2和Fe2p3/2能级的分裂说明了在成膜过程中Fe的价态发生变化,据此提出了可能的电聚合机理。同时,此修饰电极对半胱氨酸具有电催化氧化活性,并对其响应进行了研究。     

XPS和TOF—SIMS在硬盘驱动器（HDD）磁头表面微污染分析中的应用

XPS和TOF－SIMS表面分析仪器联用分析磁头臂焊接位表面有机微污染物成分,找出污染物的来源;XPS能够提供污染物中元素组成及价态信息,而TOF－SIMS能够提供其分子信息。试验证明两者联用是分析表面有机微污染物强有力的手段。     

Surface chemistry of lanthanum chromite powders II. Multivariate data modelling of the isoelectric point by the use of surface composition data achieved from X-ray photoelectron spectroscopy measurements

 Electrophoretic mobility measurements and X-ray photoelectron spectroscopy (XPS) analysis have been performed on several lanthanum chromite powders with different dopants. Principal component analysis of both deconvoluted XPS data and differentiated overall XPS spectra showed a clustering of the powders. From loading plots it was seen that high amounts of La and O on the surface gave highest isoelectric points (IEP). Partial-least-squares, multivariate response modelling was used to calibrate the IEPs from both deconvoluted XPS data and from differentiated overall XPS spectra. The best model was obtained when second-order differentiated overall XPS spectra were used, with an average predictive error of pH ± 0.25. This is promising considering that the IEP has been determined with an accuracy of pH_IEP± 0.3. When deconvoluted data was used, the average predictive error rose to pH ± 1.1. It is therefore an advantage to use multivariate data analysis which is a nonsubjective latent variable decomposing technique in contrast to deconvolution which is an even more time-consuming method for calibration of IEP values from XPS. Received: 8 October 1998 Accepted in revised form: 27 January 1999     

团簇离子枪对CH3NH3PbI3钙钛矿薄膜的影响研究

以氩离子团簇为溅射源,对采用一步旋涂法制备的CH₃NH₃PbI₃钙钛矿薄膜进行溅射实验,通过XPS分析检测样品表面Pb元素的价态变化。结果表明,新制备的钙钛矿薄膜材料表面没有检测出Pb⁰,而经过团簇离子枪溅射的样品中部分Pb²⁺还原成Pb⁰,证明了氩离子团簇刻蚀对钙钛矿材料具有破坏作用。一方面,溅射时间的增加以及团簇离子枪能量的增大均会加大钙钛矿材料的损伤程度;另一方面,离子枪团簇规模大小与溅射损伤程度呈近抛物线关系。因此,在进行此类样品表面清洁时,应尽量减小离子枪能量和溅射时间,选择较小或较大的团簇规模以减少对样品的损伤。该研究对于钙钛矿样品在进行XPS检测和数据分析时具有参考价值。     

Monitoring Fibre Surfaces with XPS in Papermaking Processes

 Recent instrumental advances have vastly improved the analysis power of X-ray photoelectron spectroscopy (XPS), which has been widely used in applied surface research for decades. In this presentation a set of XPS analysis methods well suited for problems and analytical needs encountered in papermaking technology is presented. The emphasis will be on analysis of pulps and non-coated papers. Examples given describe the use of XPS in quantification of surface lignin and extractives; an alternative approach for evaluating elemental surface distributions via the Tougaard background analysis is also presented. The experimental work and interpretations presented are based on more than two thousand XPS analyses performed at Helsinki University of Technology during 1996–2000. With strictly standardised experimental setup, state-of-the-art instrumentation and a proper combination of analysis methods XPS can yield valuable and consistent information on surface properties of natural fibers.     

Aqueous ferrofluid of magnetite nanoparticles: Fluorescence labeling and magnetophoretic control

A method is presented for the preparation of a biocompatible ferrofluid containing dye-functionalized magnetite nanoparticles that can serve as fluorescent markers. This method entails the surface functionalization of magnetite nanoparticles using citric acid to produce a stable aqueous dispersion and the subsequent binding of fluorescent dyes to the surface of the particles. Several ferrofluid samples were prepared and characterized using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), BET surface area analysis, transmission electron microscopy (TEM), and SQUID magnetometry. In addition, confocal fluorescence microscopy was used to study the response of the fluorescent nanoparticles to an applied magnetic field and their uptake by cells in vitro. Results are presented on the distribution of particle sizes, the fluorescent and magnetic properties of the nanoparticles, and the nature of their surface bonds. Biocompatible ferrofluids with fluorescent nanoparticles enable optical tracking of basic processes at the cellular level combined with magnetophoretic manipulation and should be of substantial value to researchers engaged in both fundamental and applied biomedical research.     

Polymer surface analysis: The leadership and contributions of David Briggs

David Briggs was a surface analysis pioneer. Starting in 1970 and continuing throughout his career, Dave used his expertise, vision, and ability to quickly master new surface analysis methods and solve important industrial problems. It certainly helped that he was an outstanding fundraiser in both industrial and academic settings, which ensured he always had an impressive array of the latest, most advanced surface analysis instrumentation at his disposal. He insisted on doing surface analysis correctly, and through his publications, databases, and books, he provided the community with the needed guidelines and methods to do so. In the 1970s, Dave's research was largely focused on X-ray photoelectron spectroscopy (XPS, also known as electron spectroscopy for chemical analysis [ESCA]) characterization of polymers and catalysts. He added secondary ion mass spectrometry (SIMS) to his instrumentation arsenal in the 1980s and provided many of the key, pioneering publications that described how to use this method to characterize polymer surfaces. He also did some of the first surface analysis imaging experiments in the 1980s. In the 1990s, he continued his XPS and SIMS research on polymers and advanced the surface analysis community's ability to properly interpret surface analysis data through databases and advanced data processing methods. Dave continued to publish polymer and catalysis surface analysis papers in the 2000s, but also expanded his surface analysis studies to several other topics.     

制样方法对固体粉末X射线光电子能谱测试结果的影响

为了得到准确且分辨率高的X射线光电子能谱(XPS)数据,采用不同制样方法对不同类型的导电、不导电和混合粉末的测试结果进行了研究. 从图谱半峰宽、是否有荷电、真实性、制样效率和数据处理等方面阐述不同制样方法对测试结果的影响. 试验结果表明,对于导电和不导电粉末,粘取制样略优于铟片制样,其中使用碳导电胶带制样效果更好. 对于混合样品,Scotch双面胶带粘样后的测试结果优于其他3种制样方式. 此外,铟片制样可作为数据处理时荷电校正的参考方法.     

Quantitative surface analysis by Auger and x-ray photoelectron spectroscopy

Recent developments in quantitative surface analysis by Auger (AES) and x-ray photoelectron (XPS) spectroscopies are reviewed and problems relating to a more accurate quantitative interpretation of AES/XPS experimental data are discussed. Special attention is paid to consideration of elementary physical processes involved and influence of multiple scattering effects on signal line intensities. In particular, the major features of core-shell ionization by electron impact, Auger transitions and photoionization are considered qualitatively and rigorous approaches used to calculate the respective transition probabilities are analysed. It is shown that, in amorphous and polycrystalline targets, incoherent scattering of primary and signal Auger and photoelectrons can be described by solving analytically a kinetic equation with appropriate boundary conditions. The analytical results for the angular and energy distribution, the mean escape depth, and the escape probability as a function of depth of origin of signal electrons as well as that for the backscattering factor in AES are in good agreement with the corresponding Mote Carlo simulation data. Methods for inelastic background subtraction, surface composition determination and depth-profile reconstructions by angle-resolved AES/XPS are discussed. Examples of novel techniques based on x-ray induced photoemission are considered.