From nearly 60 submissions for the 2017 WITec Paper Award, our jury selected the three best publications. They were written by scientists from Ireland, Portugal and Germany who used WITec correlative confocal Raman microscopes to study transition metal dichalcogenides, textile fibers and cement. These papers show in remarkable detail how information on the chemical and structural composition of a material, obtained through this non-destructive technique, can lead to a more comprehensive understanding of a wide range of materials.
The Gold Paper Award is conferred upon Maria O’Brien from Trinity College in Dublin (Ireland) for mapping low-frequency Raman modes of four transition metal dichalcogenides (TMDCs): MoS2, MoSe2, WS2 and WSe2. Together with Niall McEvoy, Damien Hanlon, Toby Hallam, Jonathan Coleman and Georg Duesberg, she used the Raman modes for in-plane and out-of-plane vibrations whose intensities depend on the thickness and the stacking order of the molecules’ layers. The study has shown that the low-frequency Raman modes of these materials reveal additional information compared to conventional Raman modes. The scientists are convinced: “This study presents a major stepping stone in the fundamental understanding of layered materials as mapping the low-frequency modes allows the quality, symmetry, stacking configuration and layer number of 2D materials to be probed over large areas.” They suggest using low-frequency Raman mapping for the analysis of TMDCs that show no significant changes correlated to layer numbers in the high-frequency regions of their Raman spectra.
The Silver Paper Award is given to Helena Nogueira from the University of Aveiro (Portugal). She and her co-authors Sara Fateixa, Manon Wilhelm and Tito Trindade used three-dimensional Raman imaging and surface enhanced Raman scattering (SERS) to monitor the dyeing process of linen textile fibers with methylene blue. This dye is most commonly used for blue coloring and was applied by various procedures. The scientists also visualized how the silver nanoparticles that give textiles antimicrobial properties are distributed along and within the linen fibers. The authors conclude that regarding textile production “… Raman imaging and SERS are valuable assets that complement or eventually provide unique characterization data.”
The Bronze Paper Award goes to Jonas Higl from the University of Ulm (Germany) for a Raman study on hydrating of cementitious materials. With his colleagues Marcus Köhler and Mika Lindén, he used confocal Raman microscopy to document which structures and molecules are formed during the complex process of hydrating C3S clinker. To the knowledge of the authors this study was the first one published using Raman imaging to study hydrating of cement.
The annual awards recognize outstanding scientific work published the preceding year that employed a WITec device as part of its experimental setup. The evaluation criteria include the significance of the results for the scientific community and the originality of the techniques used.
Winning Publications of the 2017 WITec Paper Award
GOLD: Mapping of low-frequency Raman modes in CVD-grown transition metal dichalcogenides: layer number, stacking orientation and resonant effects. Scientific Reports 2016, 6, 19476.
SILVER: SERS and Raman imaging as a new tool to monitor dyeing on textile fibres. Journal of Raman Spectroscopy 2016, 47, 1239. DOI 10.1002/jrs.4947
BRONZE: Confocal Raman microscopy as a non-destructive tool to study microstructure of hydrating cementitious materials. Cement and Concrete Research 2016, 88, 136.
Paper Award 2018
WITec recently announced the 2018 WITec Paper Award competition for research articles published in 2017. Scientists from all fields of application in both academia and industry are invited to submit their publications featuring results acquired with a WITec instrument to email@example.com. The deadline for submissions is January 31st, 2018.
20年来，WITec已经成长为世界知名的共聚焦拉曼成像系统制造商，也充分体现着德国品质的内涵。WITec的第一套设备——扫描近场光学显微镜（SNOM/NSOM）至今还在稳定高效地运转，伊利诺伊大学Urbana-Champaign分校Frederick Seitz材料研究实验室的资深研究员Julio Soares博士表示：“实验室当时购买了WITec的第一套NSOM设备，我们很荣幸成为WITec进一步发展的基石并得以载入WITec公司史册。在我看来，几乎不需要任何技术支持但设备还在持续运转，这本身就是一项很大的成就。
Innovations in Profilometer-guided Raman Imaging
WITec, the inventor of topographic Raman imaging, has presented at Pittcon 2017 in Chicago the next generation of its patented TrueSurface optical profilometer. The combination of surface analysis and Raman spectral acquisition enables topographic Raman imaging on rough and uneven samples. One-pass simultaneous operation makes 3D Raman chemical characterization easier and faster than ever before.
We have documented the TrueSurface in a video.
“WITec established Raman topographic imaging with TrueSurface. We then continued to innovate, leveraging the inherent strengths of our systems,” says Dr. Olaf Hollricher, Managing Director of R&D at WITec. “The overwhelmingly positive feedback from our customers confirms that chemical 3D surface analysis with TrueSurface is a successful concept with an enthusiastic following in academia and industry.”
With the TrueSurface option, Raman spectra are acquired from precisely along a surface, or at a set, user-defined distance from a surface. This makes the distribution of chemical components within the sample visible in three dimensions. Rough, inclined or irregularly-shaped samples can be investigated with the same ease as standard samples. The requirements of sample preparation can therefore be drastically reduced.
As the TrueSurface sensor actively monitors and maintains a set distance between the objective and sample surface, its closed-loop operation can compensate for any variations during measurements with long integration times. This keeps the measurement area in focus at all times and produces sharp chemical Raman images with sub-micrometer resolution.
Investigations on pharmaceutical tablet coatings, geological samples, composite emulsions, complex semiconductor structures and many other applications can benefit from the ease of use, accelerated workflow and methodological advantages provided by the new TrueSurface.
“TrueSurface is for everybody who wants to just take a sample, as it is, and put it under a microscope for chemical analysis,” explains Dr. Joachim Koenen, Managing Director at WITec. "Also, the combination of confocal Raman imaging and optical profilometry provides additional information on the chemical distribution of the sample components that are of great benefit to our customers."
When did life on Earth begin? Based on new Raman data from microfossils, scientists have dated the origin of life to at least 3,77 billion years ago.
Bubbling submarine-hydrothermal vents are believed to be the places where life on Earth emerged. Whether that happened 3.5 or 3.7 billion years ago or even further into the past is subject of intense discussion in the scientific community. Why? Because it is hard to determine whether or not chemical traces in very old sedimentary rocks– so called microfossils – are metamorphosed products of biological organisms. Dominic Papineau, a geologist who has long followed the tracks of early life, and PhD student Matthew Dodd, both from University College London (UK), along with colleagues used a microscopic approach to look for the answer. With optical microscopy they imaged thin sections from fragments found in the Nuvvuagittuq Supracrustal Belt (NSB) in Canada that once belonged to a very early oceanic crust. They identified 50 – 200 μm rosette-like structures.
Through chemical imaging performed with a WITec alpha300R confocal Raman microscope, the scientists could identify the compounds – calcite, haematite, quartz, magnetite and apatite - therein and their spatial distribution. Modern iron-oxidizing bacteria living in hot vents can form Fe-containing filaments and tubes. For that reason scientists believe that similar structures in much older rocks indicated biogenic origin. Similar structures found in Løkken jasper in Norway that geologically is somewhat younger than the NSB had already been attributed to mineralized bacteria. So the authors of the current study suggested that the carbonate rosettes they had seen are also of biogenic origin. They concluded: “Preservation in the NSV of carbonaceous material and minerals in diagenetic rosettes and granules that formed from the oxidation of biomass, together with the presence of tubes similar in mineralogy and morphology to those in younger jaspers interpreted as microfossils, reveal that life established a habitat near submarine-hydrothermal vents before 3,770 Myr ago and possibly as early as 4,290 Myr ago”.
In an email, Dominic Papineau wrote: “We used the WITec micro-Raman to map, down to sub-micron scales, the minerals associated with the oldest microfossils on Earth. This was vital to the discovery of key structures like rosettes, granules as well as minerals associated with the filamentous microfossils such as micron-size apatite, carbonate, and graphitic carbon, all of which point to the metamorphosed mineralised product of decayed microbial organic matter.”
Advanced functionality, accelerated workflow and enhanced hardware control
WITec, manufacturer of Raman and scanning-probe microscopes, presents a new operating concept with the powerful and intuitive Suite FIVE at Pittcon 2017. Sophisticated features and hands-on control transform the user experience, enabling the researcher to move from setup to results with unprecedented ease. Suite FIVE provides an integrated tool for data acquisition, evaluation and post-processing that enables researchers to quickly extract key information from their experiments. All Raman, AFM, SNOM and WITec correlative microscopy measurement modes are supported.
“Suite FIVE combines new functionality with a simplified operating concept that encompasses both software and hardware. The greater automation and intuitive interface speed up the process and improves the results of data acquisition and analysis. It’s altogether more accessible and powerful,” says Dr. Joachim Koenen, Managing Director at WITec.
Suite FIVE introduces several features for enhanced performance and usability:
A new software wizard guides the user through the complete investigation, from initial settings and acquisition through data and image post-processing. Presets and highlighted analytical paths accelerate the generation of high-quality images.
TrueComponent Analysis is a unique post-processing function for confocal Raman imaging measurements that automatically establishes the number of components in a sample, locates them in the image, and differentiates their individual spectra. This delivers meaningful, comprehensive information with one operation.
Hardware control from within the software has also been strengthened. The new handheld multifunction controller EasyLink provides a tactile and intuitive interface for directing the motorized stages, white light illumination, laser power, autofocus, cantilever positioning and objective selection with the new automated turret. This further integration of WITec’s hardware and software provides greater synergy and speed while transforming the user experience.
“TrueComponent Analysis is the standout technical achievement, without peer in the industry, though all the new features contribute to a transformed user experience. These are results-oriented developments with benefits that will be immediately apparent to the researcher,” says Dr. Olaf Hollricher, Managing Director of R&D at WITec.
WITec Suite FIVE will be presented at Pittcon 2017 Conference & Expo at McCormick Place in Chicago, Illinois from March 5th to the 9th. See all the new WITec developments at booth #1638.
More information: http://www.witec.de/products/accessories/software-witec-suite/