Hybrid X-Ray Spectroscopy-Based approach to acquire chemical and structural information of single-Walled carbon nanotubes with superior sensitivity

High-Resolution nondestructive chemical analysis of both bulk and surface of application-Ready carbon nanomaterials is needed to connect the material properties to the observed performance. This is needed to enable application-Specific tailoring of carbon nanomaterials. However, detailed studies of effects of oxidizing treatments on the chemical composition and structural integrity of carbon and on the metal seed materials are rare. We show here a hybrid X-Ray-Based study retrieving this hard-To-Access chemical and structural information of application-Ready ferrocene-Grown single-Walled carbon nanotubes and their nitric acid- A nd oxygen plasma-Treated versions. We have executed photoelectron, absorption, and X-Ray emission spectroscopy (XES) measurements in the soft X-Ray regime providing chemical and structural information with high energy resolution and throughput. We observed that the nitric acid treatment did not significantly alter the chemical state of the carbon matrix, whereas the oxygen plasma treatment was associated with strong effects and chemical conversions toward oxygen-Functionalized groups such as carboxyl. Additionally, an Fe catalyst was present before and after the oxidizing treatments at considerable concentrations as detected by both X-Ray absorption spectroscopy and XES, with a near complete conversion of Fe ²⁺ to Fe ³⁺ . Additional minor elements (metals <0.1 at. %) were detected only with XES. With this combined approach, we can study the effect of different treatments on application-Ready carbon nanomaterials' physicochemical and structural properties with unmatched precision, which helps understand the nature of these materials.