Due to their unusual electrical, thermal, and mechanical properties, two-dimensional (2D) materials such as graphene, layered transition metal disulfides, and layered black phosphorus (BP) have piqued the curiosity of researchers all over the world. In a wide range of scientific disciplines, nuclear magnetic resonance (NMR) spectroscopy is a powerful and well-established tool for compositional, structural, and functional investigation.
Alfa Chemistry provides NMR testing to evaluate the compositional and structural information of 2D materials, which is critical for understanding their unique features. Please contact us right away so that we can help you with your tests!
Why NMR
For the identification and structural resolution of organic compounds, NMR is one of the most important spectroscopic approaches. Quantitative data can be collected using internal standards due to the nature of the procedure (measuring the ratio between peak area and number of nuclei detected). 2D NMR adds to the structure elucidation by providing additional information regarding atomic connectivity. NMR is a potent and necessary method for characterizing organic substances when used in conjunction with mass spectrometry, IR, and elemental analysis.
Fig 1. 13C and 1H NMR spectra for GO powder, GO after initial gelation, and 3D graphene macroassembly. (Worsley M. A, et al. 2012)
In addition, high-resolution NMR can provide rich atomic-level characterization of surface molecules. However, because the detection limits of NMR are so low, even with high specific surface area materials, the concentration of active NMR nuclei of interest usually stays low, necessitating many hours or even days to generate a solid-state NMR spectrum with a suitable signal-to-noise ratio. As a result, low surface area materials are currently inappropriate for high resolution NMR experiments, and traditional NMR with macroscopic 2D supports is utterly out of reach.
Recently, Alfa Chemistry has been researching on NMR approaches in this field.Here, we enable the acquisition of solid-state NMR spectra of molecules immobilized on wafers by combining the recently introduced dynamic nuclear polarization (DNP) method with multi-echo (CPMG) acquisition and optimized sample formulations. Please contact us for more technical information.
Service Detail
| Testing Services | Nuclear Magnetic Resonance Spectroscopy (NMR) |
| Test Content | 1H, 13C, 19F, 29Si, 31P, 2D Spectrum |
| Sample Type | Powder / Liquid |
| Instrument Model | Bruker AvanceCore 400 MHz NMR spectrometer, Bruker Avance NEO 600 MHz NMR spectrometer |
| Lead Time | 2~3 Weeks |
Our requirements for samples are as follows:
- For Powder samples: Please provide samples larger than 20 mg.
- For Liquid samples: Please provide samples larger than 3 mL.
- For 1H testing: Please provide samples with solubility >15 mg/mL.
- For 13C testing
(1) Small molecule samples: solubility greater than 40 mg/mL
(2) Macromolecular samples: solubility greater than 100 mg/mL
(3) The chemical shift defaults to 220 ppm. If you have other requirements, please contact us.
Note:
- Alfa Chemistry cannot measure samples containing magnetic elements (iron, cobalt, nickel, manganese, etc).
- For highly volatile and mobile deuterium reagent samples, Alfa Chemistry will prepare samples for testing upon receipt of the package and does not recommend sending pre-prepared samples to avoid detection errors.
- Please contact us ahead of time for 19F, 29Si, 31P, and 2D spectroscopic examinations.
- All samples are non-refundable; if you have any specific demands, please contact us.
Reference
- Worsley M. A, et al. (2012). "Mechanically Robust 3D Graphene Macroassembly with High Surface Area." Chem. Commun. 48: 8428-8430.
Please kindly note that our products are for research use only.
