1.D.165. The Carbon Film Solid-State NanoPore (SS-NP) Family
Solid-state nanopores are widely used as a platform for stochastic nanopore sensing because they can provide better robustness, controllable pore size, and higher integrability than biological nanopores. However, the fabrication procedures, including thin film preparation and nanopore formation, require advanced micro-and nano-fabrication techniques. Takai et al. 2021 described the simple fabrication of solid-state nanopores in a commercially available material: a flat thin carbon film-coated micro-grid for a transmission electron microscope (TEM). They used two general methods for nanopore fabrication in the carbon film. The first method was a scanning TEM (STEM) electron beam method. Nanopores were fabricated by irradiating a focused electron beam on the carbon membrane on micro-grids, resulting in the production of nanopores with pore diameters ranging from 2 to 135 nm. The second method was a dielectric breakdown method in which nanopores were fabricated by applying a transmembrane voltage of 10 or 30 V through the carbon film on micro-grids. These nanopores had pore diameters ranging from 3.7 to 1345 nm. Since these nanopores were successfully fabricated in commercially available carbon thin films using readily available devices, these solid-state nanopores offer great utility in the field of nanopore research (Takai et al. 2021).
Graphene-based nanopore devices have shown potential in single molecule detection for their monoatomic membrane thickness which is roughly equal to the gap between nucleobases (Zhang et al. 2018). An adenine-based metal organic framework derived nitrogen-doped nanoporous carbon for flexible solid-state supercapacitor use has been described (Li et al. 2018). A facile method has been investigated for patterning microporous and mesoporous silica, polymer, and carbon films using a combination of lithography and solid-state chemistry (Song et al. 2008).
Structure-transport relationships of water-organic solvent co-transport occurs via a carbon molecular sieve (CMS) mechanism (Yoon et al. 2023). It uses a transport mechanism in which water-under high transmembrane pressue permeates via a Poiseuille-style mechanism, whereas p-xylene solutes in the mixture permeate via sorption-diffusion. Structure-transport relationships of water-organic solvent co-transport in carbon molecular sieve (CMS) membranes have been described (Yoon et al. 2023).