A5091914605- Gold and Silver Nanoparticles Synthesis and Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Graphene research and applications
- Near-Field Optical Microscopy
- Lipid Membrane Structure and Behavior
- Quantum Dots Synthesis And Properties
- 2D Materials and Applications
- Force Microscopy Techniques and Applications
- Plasmonic and Surface Plasmon Research
- Spectroscopy and Chemometric Analyses
- Graphene and Nanomaterials Applications
- Molecular Junctions and Nanostructures
- Biosensors and Analytical Detection
- Protein Interaction Studies and Fluorescence Analysis
- Advanced biosensing and bioanalysis techniques
- Spectroscopy and Quantum Chemical Studies
- Nanowire Synthesis and Applications
- Perovskite Materials and Applications
- Carbon Nanotubes in Composites
- Surface Chemistry and Catalysis
- Catalytic Processes in Materials Science
- Metal complexes synthesis and properties
- Advanced Fluorescence Microscopy Techniques
- Asymmetric Hydrogenation and Catalysis
- Block Copolymer Self-Assembly
ETH Zurich
2021-2025
Hangzhou Dianzi University
2024
Dow University of Health Sciences
2024
Weatherford College
2024
National Physical Laboratory
2014-2023
Liaquat University of Medical & Health Sciences
2023
Karachi Medical and Dental College
2023
Guru Jambheshwar University of Science and Technology
2022
Government Medical College
2021
Government Medical College
2019
Surface- and tip-enhanced Raman spectroscopy (SERS TERS) techniques exhibit highly localized chemical sensitivity, making them ideal for studying reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, reaction intermediates can be observed in low quantities hot spots where electromagnetic fields are the strongest, providing ample opportunities to elucidate mechanisms. Moreover, under measurement conditions, it even used trigger reactions. However, factors such...
This review provides a detailed overview of the state art in tip-enhanced Raman spectroscopy (TERS) and focuses on its applications at horizon including those materials science, chemical science biological science. The capabilities potential TERS are demonstrated by summarising major achievements disparate fields scientific research. Finally, an outlook has been given future development technique mechanisms achieving high signal enhancement spatial resolution.
Chemical mapping of a photocatalytic reaction with nanoscale spatial resolution is demonstrated for the first time using tip-enhanced Raman spectroscopy (TERS).
Confocal and surface-enhanced Raman spectroscopy (SERS) are powerful techniques for molecular characterization; however, they suffer from the drawback of diffraction-limited spatial resolution. Tip-enhanced (TERS) overcomes this limitation provides chemical information at length scales in tens nanometers. In contrast to alternative approaches nanoscale analysis, TERS is label free, non-destructive, can be performed both air liquid environments, allowing its use a diverse range applications....
Since its first experimental realization, tip‐enhanced Raman spectroscopy (TERS) has emerged as a potentially powerful nanochemical analysis tool. However, questions about the comparability and reproducibility of TERS data have emerged. This interlaboratory comparison study addresses these issues by bringing together different groups to perform measurements on nominally identical samples. Based spectra obtained, absolute relative peak positions, number bands, intensity ratios, reference...
Abstract Visualising the distribution of structural defects and functional groups present on surface two-dimensional (2D) materials such as graphene oxide challenges sensitivity spatial resolution most advanced analytical techniques. Here we demonstrate mapping a carboxyl-modified (GO–COOH) with ≈10 nm using tip-enhanced Raman spectroscopy (TERS). Furthermore, extend capability TERS by measuring local electronic properties in situ, addition to topography chemical composition. Our results...
In two-dimensional (2D) semiconductors, photoluminescence originating from recombination processes involving neutral electron-hole pairs (excitons) and charged complexes (trions) is strongly affected by the localized charge transfer due to inhomogeneous interactions with local environment surface defects. Herein, we demonstrate first nanoscale mapping of excitons trions in single-layer MoS2 using full spectral information obtained via tip-enhanced (TEPL) microscopy along Raman spectroscopy...
Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for non-destructive and label-free surface molecular mapping at the nanoscale. However, to date nanoscale resolution chemical imaging in liquid environment has not been possible, part due lack of robust TERS probes that are stable when immersed liquid. In this work, we have addressed challenge by developing plasmonically-active with multilayer metal coating structure can be successfully used within environment. Using these novel...
Tip-enhanced Raman spectroscopy (TERS) is a promising technique that enables nondestructive and label-free topographical chemical imaging at the nanoscale. However, its scope for in situ characterization of catalytic reactions liquid phase has remained limited due to lack durable chemically inert plasmonically active TERS probes. Herein, we present novel zirconia-protected probes with 3 orders magnitude increase lifetime under ambient conditions compared unprotected silver-coated probes,...
Plasmon-enhanced photocatalytic coupling reactions have been used as model systems in surface-enhanced Raman spectroscopy and tip-enhanced (TERS) research for decades. However, the role of reactive arrangement on efficiency these has remained largely unknown to date often leading conflicting interpretations experimental results. Herein, we use an interdisciplinary toolbox nanoscale TERS imaging combination with molecular-resolution ambient scanning tunnelling microscopy (STM) density...
Phase-separated polymer blend films are an important class of functional materials with numerous technological applications in solar cells, catalysis, and biotechnology. These technologies underpinned by the precise control phase separation at nanometer length-scales, which is highly challenging to visualize using conventional analytical tools. Herein, we introduce tip-enhanced Raman spectroscopy (TERS), combination atomic force microscopy (AFM), confocal spectroscopy, X-ray photoelectron...
Enhancement factor (EF) is an important measure of the quality tip-enhanced Raman spectroscopy (TERS) probes. Currently, due to presence far-field artefacts, EF often overestimated in TERS measurements. The origin this problem discussed article and a methodology for accurate measurement using bilayer sample presented characterise tips. values measured conventional proposed methodologies are compared. found be by up order magnitude when used. Finally, Ag coated probes prepared from SiO2 tips...
Lack of appropriate tools for visualizing cell membrane molecules at the nanoscale in a non-invasive and label-free fashion limits our understanding many vital cellular processes. Here, we use tip-enhanced Raman spectroscopy (TERS) to visualize molecular distribution pancreatic cancer (BxPC-3) membranes ambient conditions without labelling, with spatial resolution down ca. 2.5 nm. TERS imaging reveals segregation phenylalanine-, histidine-, phosphatidylcholine-, protein-, cholesterol-rich...
Raman spectroscopy is one of the most common methods to characterize graphene-related 2D materials, providing information on a wide range physical and chemical properties. Because typical sample inhomogeneity, spectra are acquired from several locations across sample, analysis carried out averaged spectrum all locations. This then used "quality" graphene produced, in particular level exfoliation for top-down manufactured materials. However, these have generally been developed using samples...
Non-gap TERS with a contrast of 8.5 enables mapping graphene's intrinsic defect spatial resolution 20 nm.
Optoelectronic properties of two-dimensional transition metal dichalcogenides are critically influenced by grain boundaries (GBs). However, optoelectronic behavior the GBs has not been fully understood in part due to limited sensitivity and spatial resolution conventional analytical tools. Herein, we report a detailed investigation monolayer (1L) WSe2 using powerful combination tip-enhanced optical microscopy electrical-mode atomic force microscopy. Our study reveals that work function,...
Noninvasive and label-free analysis of cell membranes at the nanoscale is essential to comprehend vital cellular processes. However, conventional analytical tools generally fail meet this challenge due lack required sensitivity and/or spatial resolution. Herein, we demonstrate that tip-enhanced Raman spectroscopy (TERS) a powerful nanoanalytical tool analyze dipalmitoylphosphatidylcholine (DPPC) bilayers human with submolecular resolution in vertical direction. Unlike far-field measurements,...
We demonstrate the capability of tip-enhanced Raman spectroscopy to probe individual point defects in graphene.
Non-destructive & label-free nanoscale mapping of newly-synthesised phospholipid molecules inside a biological cell is demonstrated using tip-enhanced Raman spectroscopy for the first time.
Relationship between plasmonic lifetime of tip-enhanced Raman spectroscopy probes and environments with different oxygen moisture content is investigated systematically.
Graphene is a highly desirable material for variety of applications; in the case nanocomposites, it can be functionalized and added as nanofiller to alter ultimate product properties, such tensile strength. However, often properties graphene location any chemical species, attached via different functionalization processes, are not known. Thus, necessarily understood why improvements performance achieved, which hinders rate development. Here, commercially available powder containing few-layer...