Liquid-phase encapsulation of α-sexithiophene (6T) molecules inside individualized single-walled carbon nanotubes (SWCNTs) is investigated using Raman imaging and spectroscopy. By taking advantage of the strong Raman response of this system, we probe the encapsulation isotherms at 30 and 115 °C using a statistical ensemble of SWCNTs deposited on a oxidized silicon substrate. Two distinct and sequential stages of encapsulation are observed: Stage 1 is a one-dimensional (1D) aggregation of 6T aligned head-to-tail inside the nanotube, and stage 2 proceeds with the assembly of a second row, giving pairs of aligned 6Ts stacked together side-by-side. The experimental data are fitted using both Langmuir (type VI) and Ising models, in which the single-aggregate (stage 1) forms spontaneously, whereas the pair-aggregate (stage 2) is endothermic in toluene with formation enthalpy of ΔH = (260 ± 20) meV. Tunable Raman spectroscopy for each stage reveals a bathochromic shift of the molecular resonance of the pair-aggregate, which is consistent with strong intermolecular coupling and suggestive of J-type aggregation. This quantitative Raman approach is sensitive to roughly 10 molecules per nanotube and provides direct evidence of molecular entry from the nanotube ends. These insights into the encapsulation process guide the preparation of well-defined 1D molecular crystals having tailored optical properties.

Fluorescence is ubiquitous in life science and used in many fields of research ranging from ecology to medicine. Among the most common fluorogenic compounds, dyes are being exploited in bioimaging for their outstanding optical properties from UV down to the near IR (NIR). However, dye molecules are often toxic to living organisms and photodegradable, which limits the time window for in vivo experiments. Here, it is demonstrated that organic dye molecules are passivated and photostable when they are encapsulated inside a boron nitride nanotube (dyes@BNNT). The results show that the BNNTs drive an aggregation of the encapsulated dyes, which induces a redshifted fluorescence from visible to NIR‐II. The fluorescence remains strong and stable, exempt of bleaching and blinking, over a time scale longer than that of free dyes by more than 104. This passivation also reduces the toxicity of the dyes and induces exceptional chemical robustness, even in harsh conditions. These properties are highlighted in bioimaging where the dyes@BNNT nanohybrids are used as fluorescent nanoprobes for in vivo monitoring of Daphnia Pulex microorganisms and for diffusion tracking on human hepatoblastoma cells with two‐photon imaging.

imaging is presented as a powerful method to acquire quantitative as well as qualitative information on lowdimensional materials. The method is, however, not widely used due to limitations of the Raman scanning instruments. Here we present a hyperspectral Raman system based on Bragg tunable filtering that is capable of global imaging with significantly reduced acquisition time and improved sensitivity compared to scanning confocal Raman microscopes. The operation principles of the instrument are presented, and the performance is benchmarked using a calibrated carbon nanotube sample. Examples of various applications are shown to illustrate the abilities of the technique to characterize samples deposited on oxidized silicon substrates, including graphene stacks prepared by chemical-vapor deposition, exfoliated MoS 2 , and carbon nanotubes filled with dye molecules. The wealth of information available through this hyperspectral Raman imaging technique opens many new ways to probe the properties of complex low-dimensional materials.

Raman spectroscopy provides rich optical signals that can be used, after data analysis, to assess if a graphene layer is pristine, doped, damaged, functionalized, or stressed. The area being probed by a conventional Raman spectrometer is, however, limited to the size of the laser beam (∼1 µm); hence, detailed mapping of inhomogeneities in a graphene sample requires slow and sequential acquisition of a Raman spectrum at each pixel. Studies of physical and chemical processes on polycrystalline and heterogeneous graphene films require more advanced hyperspectral Raman capable of fast imaging at a high spatial resolution over hundreds of microns. Here, we compare the capacity of two different Raman imaging schemes (scanning and global) to probe graphene films modified by a low-pressure plasma treatment and present an analysis method providing assessments of the surface properties at local defects, grain boundaries, and other heterogeneities. By comparing statistically initial and plasma-treated regions of graphene, we highlight the presence of inhomogeneities after plasma treatment linked to the initial state of the graphene surface. These results provided statistical results on the correlation between the graphene initial state and the corresponding graphene–plasma interaction. This work further demonstrates the potential use of global hyperspectral Raman imaging with advanced Raman spectra analysis to study graphene physics and chemistry on a scale of hundreds of microns.

<div><div><div><p>Fluorescence is ubiquitous in life science and used in broad fields of research going from ecology to medicine. Among the most common fluorogenic compounds, dyes are being exploited in bioimaging for their outstanding optical properties across a broad range of wavelengths from the UV to the near-IR. However, dye molecules are often toxic to living organisms and photodegradable, giving limited time windows for in vivo monitoring. By encapsulating organic dyes inside a boron nitride nanotube (dyes@BNNT), we achieve a passivation of the dyes against photodegradation and chemical reaction. The dyes@BNNT nanohybrids contain aggregated and ordered dyes exhibiting strong photoluminescence with signal remaining stable and exempt of blinking over a time scale of more than 10^4 compared to free dyes. Our results also suggest reduced toxicity and exceptional chemical robustness even in harsh environments. The use of these 1D dyes@BNNT nanohybrids as fluorescence nanoprobes in bio-imaging is highlighted with in-vivo monitoring experiments on living Daphnia Pulex.</p></div></div></div>

Domestic abuse can affect anyone and is recognised as a global problem that results in physical, psychological and economic harm. People who experience domestic violence often attend emergency departments after an incident, but many victims go unnoticed by healthcare professionals. This article identifies and discusses some of the challenges faced by emergency nurses in recognising and managing patients affected by domestic violence. It also discusses how addressing these challenges can improve identification of, and support for, those who have been affected.

Polarized fluorescence emission of nanoscale emitters has been extensively studied for applications such as bioimaging, display, and optical communication. Extending the polarization properties in large assemblies of compact emitters is,...

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