News & Event

Publishing recent discoveries in science and technology in peer-reviewed literature is a critical function of members of the research community. It enables us to recognize the latest progress and inspires further advances. We are looking back onto the year 2021 – on the impact Physical Electronics XPS instruments, such as  PHI VersaProbe,  PHI Quantera, and PHI Quantes, have had in supporting scientific breakthroughs.   Over 4500 scholar publications, including peer-reviewed articles and book chapters, have been published in 2021 using PHI XPS instruments. There were more than 60 papers published in the high-impact journals (Nature and Science group), with more than 30% studying novel energy-related materials, such as batteries, fuel cells, and solar cells, and 20%. on nanomaterials.   PHI XPS instruments were used to study a large range of materials of high technological and research importance -  surface treatment for inactivating SARS-CoV‑2 Virus1, oxygen evolution electrocatalysts2,3, CO2 reduction catalysts4, single-atom catalysts5,6, graphene-based materials for electrochemical materials7, ion-selective biological channels8, perovskite solar cells9,10, novel 2D materials – MXenes11 and magnetene12, novel magnetic materials based on perovskites for cooling applications13, organic multilayered semiconductors14, next-generation cathodes for lithium batteries15,16, 17, sodium-ion batteries18, lithium-ion batteries19 and solid-state batteries20.   One paper with the highest number of citations (51 citations in less than one year) published in ACS Nano is from our customers at Drexel University studying novel types of 2D materials - highly conductive Ti3C2 MXene.11 “MXenes have been utilized in various fields, including energy storage and conversion, electromagnetic interference shielding, nanocomposites, sensors, and biomedical applications. MXenes have several significant advantages over graphene and many other conducting nanomaterials: MXenes form stable colloidal solutions without additives or surfactants, and they can easily be processed using the cheapest and safest solvent−water”.  Using the PHI VersaProbe Scanning XPS Mircoprobe instrument, Mathis and co-workers demonstrated close to perfect stoichiometry and elimination of oxygen from the carbon sublattice, which may have contributed to the improved oxidation stability of the Al−Ti3C2.   XPS is becoming one of the main characterization techniques scientists use in their discovery of novel battery materials. In a collaborative work led by the Massachusetts Institute of Technology (published in Nature Energy and cited 16 times in less than a year17), a novel sulfonamide-based electrolyte was shown to enable stable ultra-high-voltage cycling of a high-nickel cathode in practical Li metal batteries. To characterize the cathode-electrolyte interface, XPS measurements were conducted on the surface of the cathodes after the 100 cycles. Authors compared C 1s, and F 1s spectra from a cathode cycled in the novel electrolyte to that in a reference and discovered more  LiF-like inorganic components and less organic components pointing to the less reactive and corrosive nature of the novel electrolyte.   Fig. 1 XPS analysis for the cathodes cycled in the novel sulfonamide-based electrolyte (f and h) and reference (e and g) electrolytes for 100 cycles. PVDF= polyvinylidene fluoride   Another important collaborative work between researchers at Zhengzhou University, Penn State University, and the University of Texas at Austin (published in Nature communication and cited nine times in less than a year21) focuses on lithium-sulfur (Li–S) batteries that couple a Li anode with a sulfur (S) cathode. Authors address two significant problems in Li-S batteries - interfacial instability of the lithium-metal anode and polysulfide migration from the cathode - by using a promising electrolyte additive BTT, which involves an exchange reaction on the Li-metal anode and electrochemical polymerization on the sulfur cathode.   Fig. 2 XPS data for the recharged cathode after 5 cycles at 0.05C rate for the BTT cell (top), and the discharged cathode after 5 cycles for BTT cell (bottom) They used the PHI VersaProbe instrument for depth profile characterization of the dual solid-electrolyte interface in asymmetric Li cell after cycling. The depth profile provided information on the chemical environment between Li and the S-H functional group of BTT based on the Li, S, and F spectra. The homogeneity of Li3-BTT and the apparent change of Li-F demonstrated that the BTT SEI is composed of organic lithium and inorganic lithium compounds. “Compared with the BTT electrode, the SEI formed in the commercial electrolyte is fragile and has poor ionic conductivity, with uneven composition. It also includes more reduced products, such as SO32- and S2- (from LiTFSI) in the S 2p spectrum and side reaction products of LiOH (55.0 eV in Li 1s spectrum), Li–O, and Li–F in the Li 1s spectrum.”   XPS was also collected to further understand the chemical composition of the charged product. The S 2p peaks of the bridged S (S–S) and the S bonded to the phenyl ring (C-S) are found at 164.1 eV and 163.5 eV in the recharged product, respectively. The presence of Li2S and Li2S2 are due to the incomplete charging of the cell.   We are very proud to be a part of the exciting discoveries our customers make. Read more about them in the papers cited below. https://doi.org/10.1021/acsami.1c15505 https://doi.org/10.1038/s41560-021-00925-3 https://doi.org/10.1002/adfm.202106229 https://doi.org/10.1038/s41467-021-25573-9 https://www.science.org/doi/10.1126/sciadv.abd9210 https://doi.org/10.1038/s41557-021-00734-x https://doi.org/10.1038/s41598-021-01154-0 https://doi.org/10.1021/acsnano.1c07210 https://doi.org/10.1038/s41467-021-26754-2 https://doi.org/10.1038/s41565-021-01010-2 https://doi.org/10.1021/acsnano.0c08357 https://www.science.org/doi/10.1126/sciadv.abk2041 https://doi.org/10.1038/s41598-021-99755-2 https://doi.org/10.1002/smtd.202001264 https://doi.org/10.1021/acsami.1c15271 https://doi.org/10.1038/s41467-021-26815-6 https://doi.org/10.1038/s41560-021-00792-y https://doi.org/10.1002/adfm.202109694 https://doi.org/10.1038/s41467-021-26073-6 10.33774/chemrxiv-2021-4dnn0 https://doi.org/10.1038/s41467-021-23155-3      

On November 5th, 2021, PHI China had successfully held the "ULVAC-PHI Surface Analysis Application and Academic seminar User Meeting (Guangdong)" at Shenzhen, Guangdong. This meeting focused on the application of surface analysis and its technology. Many experts and professors were invited to exchange reports. This conference was not only an offline communication, but also conducted an online report live broadcast, which attracted the participation of many online and offline universities and enterprises, and a good academic exchange atmosphere has been established.   With the rapid development of high and new technology in the fields of materials, energy, microelectronics, information industry and environment, surface science has become one of the most active disciplines in the world, and the demand for surface analysis technology is also increasing. XPS/TOF-SIMS/AES have all become effective surface analysis techniques, and are widely used in basic scientific research, advanced material development, high-precision technology and other fields, which has promoted the research and development of materials science. This conference not only interpreted some of the current statuses, problems and challenges of the surface analysis industry from a macro perspective, but also introduced and shared the application and case studies of surface analysis instruments. Combining theory with practice, face-to-face exchanges and discussions were on-site.   Group photo   Professor of Sun Yat-sen University  Mr. Jian Chan   Professor of Southern University of Science and Technology  Mr. Ding Sun An     Professor of Institute for Advanced Study, Shenzhen University  Mr. Zhao Wei   Engineer of Southern University of Science and Technology  Ms. Zhang Juan   Senior Engineer of SAE Technologies Development (Dongguan) Co., Ltd.  Ms. Wang Mu    Executive Director of PHI (China)  Mr. Wensly Yip   PHI CHINA will uphold its original aspiration and continue to help the development of the surface analysis industry. In the future, we will continue to hold more online and offline seminars, so please stay tuned!   You may watch back the video by accessing Technical Info > Technical video      

(This page is in Chinese only.  For details, please kindly contact our representative.)   致各位老师、专家和单位人员： 首为积极推动表面分析应用技术的发展，促进表面分析技术与其它学科的融合，更好地结合表面分析技术解决问题，同时加强同行之间交流与合作，展示相关的新成就、新进展，PHI CHINA 拟于 2021 年 11 月 5 日在广东深圳举办“2021 表面分析应用与学术研讨会暨广东分会”。此次会议邀请了多位在表面分析应用领域具有较深的造诣的专家、教授们进行交流报告，旨在建立表面分析的交流平台，形成研讨的学术氛围，让思想碰撞出火花，并共同提升理论与技术水平，促进表面分析科学研究队伍的壮大。 本次会议将邀请国内表面分析领域知名专家学者分享学术报告，展示相关的新成就、新进展，探讨技术理论，共同提升理论与技术水平。PHI CHINA 热忱欢迎广大专家学者和科研人员积极参与会议，分享、交流、学习、创新。   现就本次会议的相关安排通知如下：   一、会议时间与地点 时间：2021 年 11 月 5 日 09:00-18:00 地点: 深圳坂田希尔顿欢朋酒店（一号会议室） 广东省深圳市龙岗区坂田街道坂雪岗大道 4001 号 交通: 距离深圳北站 9 公里 / 距离深圳宝安机场 35 公里   二、参会信息 1. 参会报名 参会请扫下方二维码完成报名   2.  参会费用和食宿安排 本次会议不收取会务费，参会人员的食宿费和交通费用需自理。会务组以优惠价格为本次会议联系了一定数量的房间，参会人员如有订房需求，请联系会务组工作人员： 张伟 (电话：18500084171 , 邮箱:william.zhang@coretechint.com)*请大家尽量在 2021 年 11 月 2 日前完成订房。    三、会议主题 • XPS、AES、TOF-SIMS 等表面分析测试技术 • XPS、AES、TOF-SIMS 数据分析及数据处理 • 表面分析技术及其在新材料中的应用 • 新能源、新材料表征技术 • 先进结构技术、前沿交叉科学中的表面分析技术应用 • 表面分析科学在双一流建设中的作用等   四、会议日程及安排 时间 事项 报告人 9:00am – 9:10am 会议开幕致辞 叶上远 总经理 PHI CHINA 9:10am – 9:50am 无损深度分析技术（HAXPES）在表界面研究中的应用 鞠焕鑫 博士 PHI CHINA 9:50am – 10:30am 广东表面分析技术概况 陈建 教授 中山大学 10:30am – 10:50am 茶歇+合照   10:50am – 11:30am 目前表面分析遇到的一些问题和挑战 丁孙安 教授 南方科技大学 11:30am – 12:10pm AES 高空间分辨能力及应用 丁志琴 工程师 PHI CHINA 12:10pm – 14:00pm 午餐时间   14:00pm – 14:40pm 木质素单体电催化选择性加氢催化 赵伟 教授 深圳大学 14:40pm – 15:20pm XPS 测试技术的操作及案例分享 张娟 工程师 南方科技大学 15:20pm – 15:40pm 茶歇   15:40pm – 16:20pm 荷电中和技术及差分荷电问题探讨 鞠焕鑫 博士 PHI CHINA 16:20pm – 17:00pm TOF-SIMS 在电子行业的应用 王牡 高级工程师 东莞新科技术研究开发有限公司 17:00pm – 17:40pm Introduction of the latest PHI VersaProbe 4 叶上远 总经理 PHI CHINA 17:40pm – 20:00pm 晚宴     五、防疫需求 为配合当地及酒店防疫需求，参会人员需出示 14 天内未到过中高风险区的行程记录。望参会人员配合，谢谢！   六、会务组联系方式 张 伟 (电话：18500084171，邮箱：william.zhang@coretechint.com) 吴 婷 (电话：18061250085，邮箱：noreen.wu@coretechint.com)   高德英特（北京）科技有限公司 ULVAC-PHI Incorporated

(This page is in Chinese only.  For details, please kindly contact our representative.)   时间：9月18日15:00-17:00 主题：不忘初心，创无止境I  PHI XPS-全面高性能电子结构综合分析平台 主讲人：Wensly 嘉宾：保秦烨 平台：腾讯会议+B站直播 ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………   ULVAC-PHI,INC.在表面分析领域有着50余年的发展历史，专注于高灵敏、高能量分辨和高空间分辨技术研发，开发了一系列具有独特技术优势的表面分析设备，包括X射线光电子能谱(XPS)、反光电子能谱(IPES)、俄歇电子能谱(AES)、飞行时间二次离子质谱(TOF-SIMS)以及串联质谱(Tandem MS/MSMS)等，这些分析设备可以提供元素组分、化学态、电子结构和分子结构等关键信息，为表面特性研究及材料/器件性能提升起到了重要的作用。   其中在X射线光电子能谱仪领域，PHI研发了独具特色的扫描聚焦型XPS，X射线束斑优于10 um，实现了对样品的元素组分及化学态微区分析功能，同时束斑可调的特点也兼顾了对常规样品的测试，成为科学研究、质量控制和失效分析等领域的利器。PHI一直秉持为用户提供最先进的表面分析技术的初心，在技术创新的道路上从未停歇，努力为用户提供从小束斑微区分析到大束斑高通量分析的完美XPS仪器。   由PHI CHINA举办的新的一期表面分析技术专题讲堂，将于9月18日15:00-17:00开展。高德英特中国区执行总监叶上远Wensly将带来“不忘初心，创无止境I  PHI XPS-全面高性能电子结构综合分析平台”的主题报告，跟大家分享PHI XPS的最新进展。   同时，我们还邀请了华东师范大学的保秦烨教授作为嘉宾，将为大家带来“光电子能谱在有机光伏、钙钛矿光伏研究中的应用”的报告，主要介绍UPS/XPS/IPES能谱技术，以及我们基于能谱技术在软物质光电材料(有机半导体，杂化钙钛矿)表/界面物性方面的研究进展。     参会方式： 时间：9月18日 腾讯会议：515 857 566 https://meeting.tencent.com/s/XCmHDdn8YiUr B站直播： https://live.bilibili.com/21820621    

(This page is in Chinese only.  For details, please kindly contact our representative.)   随着材料、能源、微电子、芯片半导体、信息产业及环境领域等高新技术的迅猛发展，表面科学目前已经成为国际上最为活跃的学科之一，对于表面分析技术的需求也日益增多。X射线光电子能谱(XPS)是一种有效的表面分析技术，已经广泛应用于基础科研、先进材料研制和高精尖技术等领域，极大地促进了材料学的研究与发展。PHI X射线光电子能谱仪采用扫描聚焦型X射线，最小X射线束斑可以小于10 um，同时还可以集成俄歇电子能谱（AES），进一步将空间分辨能力提升到100 nm。通过XPS和AES的结合，PHI XPS在材料表面化学成分分析、表面元素定性和半定量分析、元素深度分布分析及微区分析等方面都具有优越的表现。   近日，深圳市八六三新材料技术有限责任公司购入了PHI 配备AES功能的X射线光电子能谱仪，并邀请PHI开展“质量控制与失效分析利器 - PHI 5000 VersaProbe XPS/AES 表面分析仪应用详解”网络会议，着重给大家介绍PHI XPS及AES在高科技产业中的质量控制和失效分析方面的应用。本次网络讲座将通过腾讯会议开展，同时在哔哩哔哩网站进行直播，在此欢迎大家积极参与，多多交流互动！   参与方式 1、时间： 9月4日（星期五）14：30-16：00   2、参与方式： 腾讯会议 会议ID：186 341 371 https://meeting.tencent.com/s/7Pwp1jX8JdUc   ​B站直播间 扫描二维码关注直播间   点击链接：https://live.bilibili.com/21820621   深圳市八六三新材料技术有限责任公司简介　 深圳市八六三新材料技术有限责任公司是2001年由国家科技部批准成立的国家级材料研发和分析检测机构，拥有XPS、SEM、XRD、XRF、EDX、SIMS、GC-MS、ICP、HPLC等数百台精密检测设备，设备原值4000多万元。具有中国合格评定国家认可委员会CNAS认可、计量认证CMA和国军标认证资质及武器装备科研生产许可证认证。设有博士后创新基地、广东省博士工作站、深圳市技师工作站，培养了一批经验丰富的高端人才；依托深圳市新材料行业协会及发起延伸成立的深圳市电池、真空技术、石墨烯、3D打印、建材、印刷电路板、光电材料等系列协会，与富士康、华为、中兴、比亚迪等超大规模企业建立业务合作。   PHI公司介绍 PHI公司(Physical Electronics)自1969年成立，曾一度成為在美国PE(Perkin Elmer)公司的专业表面分析仪器部门，于2003年被日本真空ULVAC-PHI收购。ULVAC-PHI作为全球最专业的表面分析仪器制造商，拥有50余年的表面分析设备研发和生产历史，专注于研发生产表面分析仪器，其产品包括光电子能谱仪(XPS)，俄歇电子能谱仪(AES)，飞行时间二次离子质谱仪(ToF-SIMS)和动态二次离子质谱仪(D-SIMS)。PHI CHINA致力于为用户提供先进技术和优质服务，与大家携手推动表面分析技术的应用和发展。     You may watch back the video by accessing Technical Info > Technical video

(This page is in Chinese only.  For details, please kindly contact our representative.)   表面分析技术包括了飞行时间二次离子质谱、X射线光电子能谱等技术，在生物医药的研发和生产过程中，对于药物、细胞等表面以及一定深度的成份信息的表征具有非常重要的意义，也是生物医药领域必不可少的分析手段。无损三维成像技术主要包括X射线三维显微镜，可对样品内部结构与组分在三维空间进行的定量表征。 为了促进表面分析技术与三维成像技术和生物医药领域的碰撞，产生出新的科学火花，PHI CHINA将联合仪器信息网、束蕴仪器和布鲁克，在8月28日13:30-17:30开展“表面分析&无损三维成像技术在生物医药领域的应用研究”会议。 本次会议特设300个免费参会席位，有问必答。欢迎积极参与！   主办单位：仪器信息网&束蕴仪器 协办单位：高德英特(北京)科技有限公司&ULVAC-PHI&布鲁克     会议日程： 08月28日  “表面分析技术&无损三维成像技术在生物医药领域的应用研究” 13：30-14：10 表面分析技术在生物医药领域的应用之概述  叶上远 高德英特中国区执行总监 14：20-15：00 表面分析技术在生物医药领域的应用研究（一）张薰匀 应用科学家（ULVAC-PHI） 15：10-15：50 表面化学对细胞-基底相互作用的影响和研究  薛景中台湾中央研究院 研究员 16：00-16：40表面分析技术在生物医药领域的应用研究（二）张薰匀 16：50-17：30 三维X射线显微镜在医药领域的应用研究 王金波 布鲁克X射线荧光事业部         本次会议由仪器信息网&束蕴仪器主办，请参照指南进行报名 一、报名贴士（敷衍填写将不予审核）       1、请认真填写各项，您的手机号为您的参会凭证。      2、报名后，参与直播可获取会后资料、加交流群。   二、参会方式（手机电脑均可参会）       1、直播前一天，助教会统一审核。审核通过后，会发送参会链接给报名手机号。      2、如无法正常参会，请“备注会议题目”加【微信wljt-02】，帮您解决。   三、会议资料（交流群，会后视频）       1、报名并参与直播可与专家问答交流。会议群会在直播当天展示，会议ppt无法提供。      2、关注“PHI与高德公众号”，获取会后回放视频。       报名链接： https://www.instrument.com.cn/webinar/meetings/BM828/             You may watch back the video by accessing Technical Info > Technical video

At the invitation of Prof. Jian Feng Wu, from school of Chemistry and Chemical Engineering, Lanzhou University, the online lecture on “Research and Application of Quasi-in-situ/In-situ Analysis of X-ray Photoelectron Spectroscopy” organized by PHI CHINA was successfully held on August 13th. X-ray photoelectron spectroscopy (XPS) is a widely used analysis technique by the detection of photoelectrons emitted from the surface of samples excited by X-ray. XPS can obtain the information on the composition and chemical state on the sample surface. Dr. Huanxin Ju systematically reported the latest development and application of XPS from three aspects: excitation X-ray source, sample environment and detection information:   The development of XPS based on high-energy X-ray not only realizes non-destructive depth analysis, but also provides more possibilities for in-situ experiments. The development of ambient pressure XPS and the in-situ research on solid-gas interface and solid-liquid interface. X-ray with small beam size provides the possibility for inhomogeneous samples and micro XPS analysis. The combination of XPS and working environment (such as high temperature and high pressure, voltage, light, etc.) to realize testing under working conditions. Comprehensive electronic structure information detection for characterization of semiconductor samples.   You may watch back the video by accessing Technical Info > Technical video

In the last lecture of the PHI CHINA “Tips Sharing for XPS Series (1) Precise Navigation for Micro-area Analysis – SXI”, we learned together how to use the SXI function of XPS analysis to achieve precise navigation and precise analysis. With the discussion, we’ve made it clear that in the experimental analysis, the most important point is that the beam spotted size of the incident X-ray source needs to be selected, corresponding to the size of the sample. On August 5th, 2020 (Wednesday), PHI CHINA will continue to use "SXI" as the theme, extended the content of the first online lecture, and shared more SXI functions of XPS analysis experiments.   In XPS experiments or other analysis techniques, it is the most basic and important thing to know where the signal is really coming from. Therefore when doing experiments, how do analysis tools define the so-called "analysis area"?   For example, on the SEM/EDS instrument, analysis position is defined by observing the SEM image derived from the primary analysis electron beam source. Because the observation source and the analysis source are completely homologous and the same optical path, the definition of "analysis area" is completely accurate. For XPS, the most commonly used method is: when the sample is in the analysis room and shoot the sample using a CCD camera to define it as "analysis area". However, the actual situation is that CCD is not an analysis beam source, then what kind of problem does this have for the analysis results? (See below figure)           The real morphology of the sample in SXI on the right is not visible from the optical image.   This time, we take a variety of real samples as examples (such as powder, etc.) to actually operate and demonstrate how to perform XPS analysis. Therefore, everyone can understand more intuitive and profoundly :"Define analysis area and signal source area" is this most basic concept in the entire analysis process, even during data processing.  Our ultimate goal is to obtain the most accurate and correct XPS analysis results.      Mr. Wensly Yip 叶上远 – 高德英特 中国区 执行总监PHI (China) Limited Executive Director PHI (China) Limited 高德英特(北京)科技有限公司                 Narration in the online lecture by Mr. Wensly Tip     On 4th July 2020, we have brought the web class of the technical skill sharing of Accurate Navigation on XPS analysis by the function of SXI. With that, we have learnt and known that how important it is to have the capabilities to vary the primary analysis spot size so that fitting to the require analyzes / analyzed feature.     This time, we hope to bring you another online course that extends this concept. In real life, for XPS experiments and even many other analysis techniques, it is very important to know where to analyze and where the signal really comes from. Therefore, the most important point is simplicity: How analysis tools define/define the so-called "analysis area".     For example, on SEM/EDS instruments, the analysis position is defined based on the SEM image from the main electron beam. So, it is always completely accurate. For XPS, the common and most commonly used method is using a CCD camera to photograph the sample while the sample is in the analysis room. However, the reality is that the CCD is not the main beam.     In this extended course, we will take the real example of / as an example to demonstrate how to conduct a real experiment of XPS analysis. When considering the very basic concept of "defining the analysis area", after all, it returns to the theme of "precise navigation and precise analysis". Ultimately, this will help us obtain the most accurate and correct XPS analysis results.   To review Powerpoint of this topic, you may access Technical Info > Application Notes   You may watch back the video by accessing Technical Info > Technical video

As an important surface analysis method, X-ray photoelectron spectroscopy (XPS) can perform qualitative and quantitative analysis on the elemental composition and chemical state of the sample surface. Now it has been widely used in scientific research and industrial production. In previous online lectures, we explained “XPS/UPS/LEIPS fundamental review and technologies features with applications”, “XPS instrumentation, sample preparation and transportation”, “XPS data interpretation and how to use MultiPak” and “XPS instrument daily maintenance & troubleshooting” to everyone. These lectures received widespread attention and praises.  To have a job well done, a workman must have his tools in excellent condition. We will start a new series of 30 minutes online lectures, sharing the unique tips of advanced XPS technology to you.   Learning how to understand the structure-effect relationship of the microscopic scale is the key of improving material and device performance, which is also focus of current research. In scientific research and failure analysis, it is found that surface of the material does not exist uniformly on the micro scale, but is the localization of the active area. Therefore, micro-region analysis is particularly important for truly understanding the structure-effect relationship. Conventional XPS analysis usually uses X-ray beam spots of hundreds of microns to obtain average information on the sample surface, which is difficult to analyze localized features.  How to accurately locate the local feature structure is a prerequisite for microanalysis.     In this online lecture series, we will focus on the precise navigation tool of XPS microanalysis-SXI (X-ray induced secondary electron images): SXI and XPS have the same origin, same optical path, and the same detector, which can ensure accurate positioning of the analysis point with no error and can observe the surface contamination and topographic features that are difficult to detect by the optical system. Through SXI imaging, it can be used to define point analysis, multiple analysis points, line analysis and area analysis on the region of interest.     During this online lecture, we actively interacted with audiences while explaining the knowledge which has received widespread attention. Please keep following PHI CHINA.  More information and knowledge about XPS tips are coming soon.   You may watch back the online lecture video > Technical video

With rapid development in science and technology in recent years, advanced surface analysis technology has become a necessary experimental technology for surface characteristics research in the fields of materials, energy, catalysis, microelectronics, and semiconductor industries. XPS is an important scientific instrument in surface analysis, which can provide surface composition and chemical state information.  It is widely used in scientific research and high-tech industries and take an important role to solve complex problems.   As a new type of solution-processable ionic semiconductor material, metal halide perovskite has become a hot material in the field of optoelectronic research in recent years due to its advantages of adjustable band gap, high defect tolerance and simple preparation. However, metal halide perovskites with a spatial structure similar to lithium ion conductor lanthanum lithium titanate (Li3xLa2 / 3-xTiO3) have little research on lithium ion doping characteristics and related applications.   Recently, the team of Professor Yao-Hongbin, School of Chemistry and Materials Science (SCMS) of University of Science and Technology of China (USTC), in collaboration with Associate Professor Zhang, Guozhen and Dr. Ju, Huanxin of PHI CHINA Nanjing Laboratory. They have made significant progress in the construction of metal halide perovskite lithium conducting layers and stabilizing lithium metal batteries. The team of Prof. Yao utilized the advantages of chlorine-based metal halide perovskite wide band gap, good film formation and simple preparation to develop a gradient lithium conductive layer based on the metal halide perovskite. Therefore, the isolation of the lithium metal anode and the electrolyte is achieved, which greatly improves the cycle stability of the lithium metal battery. The result was published in Nature's comprehensive journal Nature Communications under the title "Metal chloride perovskite thin film based interfacial layer for shielding lithium metal from liquid electrolyte" (DOI: 10.1038 / s41467-020-15643-9).   Fig. 1 Mechanism exploration of Li+ ion migration through the lattice of metal chloride perovskite.   A Schematic illustration of the mechanism of Li ions’ intercalation into perovskite lattice, the formation of perovskite-alloy gradient Li ion conductor and the deposition process. b hypothetical migration pathway of Li+ ion and corresponding potential energy. c, Cyclic voltammetry comparison of the cells spin coated with metal halide perovskite film.   The researchers found that chlorine perovskite (MASnCl3 and MAPbCl3) prepared by spin coating method has the characteristics of accommodating and transporting lithium ions (Fig. 1a). DFT and CI-NEB theoretical calculations show that the transport energy barrier of lithium ion in the lattice of metal halide perovskite MASnCl3 is 0.45eV in the direction of [001], which is equivalent to the know lithium-ion conductors such as Li4GeS4 (0.53eV) and γ-Li3PS4 (0.49 eV) (Fig. 1b). According to the result of the simulation, with the methylammonium [CH3NH3]- oriental adjustment, the shuttle behavior of lithium ion in perovskite lattice follows the hole between [SnCl6]4-octahedron and methylamine ion [CH3NH3]- . Through the cyclic voltammetry (Fig. 1c) and depth analysis of XPS, the researchers found that, lithium ion can be inserted into metal halide perovskite lattice, and can carry out alloying/dealloying reaction reversibly, forming a 300nm thick Li-Sn alloy layer at the bottom, constituting an unique perovskite –alloy gradient structure. The Li-Sn alloy layer has a higher lithium ion mobility coeffiecient (~~10-4 cm2 s-1), meanwhile, the byproduct LiCl has electrical insulation, protecting the upper layer of perovskite framework from collapse. This unique perovskite-alloy gradient structure is beneficial to the deposition/ desorption of lithium ions.   Fig. 2 a Schematic illustration of the mechanism of Li ions’ intercalation into perovskite lattice, the formation of perovskite-alloy gradient Li ion conductor and the deposition process. b hypothetical migration pathway of Li+ ion and corresponding potential energy. c, Cyclic voltammetry comparison of the cells spin coated with metal halide perovskite film.   Furthermore, the researchers have developed a convenient solid-phase transfer method to transfer the high-quality chlorine based perovskite (MASnCl3 and MAPbCl3）films prepared by spin coating method to the surface of lithium foil in situ, forming a lithium conducting layer with gradient structure (Fig. 2a). The metal halide perovskite lithium conducting layer can improve the interface between electrolyte and lithium metal, achieve dense lithium deposition and stripping, and avoid the growth of lithium dendrite and the pulverization of lithium metal electrode (Fig. 2b). The final electrochemical cycle test of lithium metal full cell shows that under the protection of metal halide perovskite conductive lithium layer, even under the strict conditions of poor lithium (50 μm) and limited electrolyte (20 μ L mah-1) and 2.8 mAh cm-2 surface capacity, the capacity of lithium cell without protective layer has been reduced to 40% after 50 cycles (Fig. 2 c).   In the process of XPS characterization of “perovskite-alloy-lithium metal” gradient interface structure, the partial reduction of B-site ions in ABX3 perovskite will be caused by depth profiling, which makes the depth XPS characterization based on Ar ion sputtering unable to truly and objectively reflect the change of the valance state of B-site elements at different depths (Fig. 3a,b). In this regards, using mechanical stripping method, the chemical composition of the interface layer at different depths are exposed. The researchers used Kapton tape for mechanical stripping under the protection of inert atmosphere in glove box (Fig. 4a). At the same time, the prepared samples are transferred from the glove box to the XPS experimental device of PHI China Nanjing Laboratory though the inert atmosphere transfer chamber. The environmental sensitive samples in the whole sample transfer process are always under the protection of inert atmosphere, ensuring the reliability of the experimental results (Fig. 4b).   Fig. 3 Partial reduction of B-site ions of ABX3 perovskite caused by Ar ion sputtering   Fig. 4 a, The perovskite-alloy interface at different depth exposed based on the mechanical stripping method. b Using inert atmospheric transfer vessel to transfer the prepared samples from the glove box to the XPS Instrument.   The researchers found that the “perovskite-alloy” interface made by solid phase transfer method in the initial state, the B-site elements on the surface show the same oxidation state (Sn2+ and Pb2+) as the original perovskite films. After the first mechanical stripping, the perovskite layer on the surface are removed, the alloy layer (Sn0+ and Pb0+ , from Li-Sn alloy and Li-Pb alloy) at the bottom of perovskite is exposed. Along with the times of mechanical stripping, the ratio of perovskite is decreasing gradually while the ratio of alloy is increasing gradually. The researchers used a depth profile XPS analysis to prove the “perovskite-alloy-lithium metal” gradient structure of the perovskite interface on the lithium metal surface (Fig. 5b,c). At the same time, the LiCl insulation layer formed at the bottom also proved by an XPS analysis (Fig. 6). LiCl insulation layer can effectively prevent the destruction of perovskite by electrons from the electrodes, only allow lithium ion passing through, this further promoted the stability of the perovskite interface layers during the circulation.   Fig. 5 The depth profile XPS analysis of the perovskite-alloy interface layer based on mechanical stripping method.   Fig. 6 The Li 1s binding energy of the perovskite interface at the bottom.   This work is the first attempt to apply metal halide perovskite material to a lithium metal halide perovskite material, and provides strong evidence of the high lithium ion conductivity of the metal halide perovskite material. At the same time, it provides new ideas for the design of new solid electrolytes and high-performance lithium metal batteries.   The first co-authors of the paper are Yin-Yichen, a doctoral student; Wang, Qian, a master student of SCMS and Yang-Jingtian, an undergraduate student in the Junior College.  Prof. Yao, Associate Prof. Zhang from SCMS and Dr. Ju from Nanjing Laboratory of PHI CHINA are co-corresponding authors of the paper. The research was supported by the National Natural Science Foundation of China, the Ministry of Science and Technology, Hefei National Laboratory for Physical Sciences at the Microscale and USTC Center for Micro Nano Research and Fabrication.   Article link: https://www.nature.com/articles/s41467-020-15643-9   Introduction of Research Group of Professor Yao, Hong bin Professor Yao-Hongbin, professor and doctoral supervisor of the Department of Applied Chemistry, USTC. He graduated from Department of Chemistry, USTC in 2006.  In 2011, he obtained a Ph.D. in inorganic chemistry from Hefei National Laboratory for Physical Sciences at the Microscale while tutor was Professor Yu, Shuhong. From 2012 to 2015, he conducted postdoctoral research work at Stanford University and cooperated with Professor Cui, Yi. From August 2015 to present, he engaged in the research of new functional metal halides in energy storage and photoelectric conversion applications at Department of Applied Chemistry, USTC.   A multifunctional structure design system for functional metal halide crystals is established, and a method for adjusting the physical and chemical properties of metal halide crystals by effectively combining structural elements is proposed. The synthesis method of high-quality nanocrystals with metal halides of red, green and blue solid colors has been developed and applied to the construction of high-efficiency electroluminescent diodes. A highly linear metal halide luminescent material is designed to achieve complete polarization of fluorescence. Based on the metal halide frame structure, the construction of a new type of solid electrolyte is realized and successfully applied to the interface protection of metal lithium anodes.   In recent years, he has published more than 120 papers in high-impact academic journals in Chem. Soc. Rev., Angew. Chem., JACS, Nature Commun. Nano Lett., Adv. Mater., ACS Nano. Among them, 26 papers were rated as highly cited papers by ESI. The paper has been cited by SCI more than 11,000 times, and the H factor has reached 56 times. The original achievements have been featured reports and special reviews by professional media such as Nature, NPG Asia Materials, Materials Views China, Chemistry views, etc.   Research Group website: http://staff.ustc.edu.cn/~yhb/   Introduction of PHI CHINA Nanjing Laboratory PHI CHINA Nanjing laboratory was established in December, 2018.  It is committed to provide technical support for PHI CHINA surface analysis equipment and promoting the application of advanced surface analysis technology in scientific research and high-tech industries through cooperation. At present, the XPS system in PHI CHINA laboratory integrates multiple surface analysis technologies (XPS-UPS-IPES-GCIB): the unique scanning-focus XPS can provide high surface sensitivity        During the epidemic, PHI CHINA Nanjing Laboratory held several the online surface analysis technology lectures, including XPS, AES and TOF-SIMS related analysis technology principles, sample preparation and data analysis. If you want to make better use of these surface analysis technologies to solve scientific problems in scientific research, please visit our WeChat account to watch the lectures playback.   Article link: https://www.nature.com/articles/s41467-020-15643-9