A deep-UV optical circuit includes a laser emitting light wavelengths () below 250 nm. The circuit also includes a graphene optical cable formed of an optic core formed of a gas or vacuum having an index of refraction ranging between 1.000 and 1.002 and a cladding layer formed of a graphene cylinder made of a contiguous lattice of covalently-bonded carbon atoms surrounding the optic core. The circuit also includes an optical detector circuit configured to detect the light. The graphene optical cable optically couples the laser to the optical detector circuit, where the optical cable transmits light wavelengths () below 250 nm as graphene has an index of refraction less than 1 for light wavelengths () below 250 nm.

A flexible all-solid state supercapacitor is provided that includes a first electrode and a second electrode, and a flexible nanofiber web, where the flexible nanofiber web connects the first electrode to the second electrode, where the flexible nanofiber web includes a plurality of flexible nanofibers, where the flexible nanofiber includes a hierarchal structure of macropores, mesopores and micropores through a cross section of the flexible nanofiber, where the mesopores and the micropores form a graded pore structure, where the macropores are periodically distributed along the flexible nanaofiber and within the graded pore structure.

A flexible all-solid state supercapacitor is provided that includes a first electrode and a second electrode, and a flexible nanofiber web, where the flexible nanofiber web connects the first electrode to the second electrode, where the flexible nanofiber web includes a plurality of flexible nanofibers, where the flexible nanofiber includes a hierarchal structure of macropores, mesopores and micropores through a cross section of the flexible nanofiber, where the mesopores and the micropores form a graded pore structure, where the macropores are periodically distributed along the flexible nanaofiber and within the graded pore structure.

Fuel cell catalyst layers and methods of making the same are disclosed. The fuel cell catalyst layer may include a catalyst substrate including a non-woven mat of carbon nanofibers, each having a surface portion and a bulk portion bounded by the surface portion. A plurality of catalyst particles may be included in the catalyst layer, at least a first portion of which are fully embedded within the bulk portion of each of the carbon nanofibers. The method may include spinning a composition including a base polymer, a solvent, and a catalyst precursor into a non-woven fiber mat having the catalyst precursor embedded therein. The mat may then be carbonized to form a carbon fiber substrate and the catalyst precursor may be reacted to form catalyst particles embedded in the substrate. Embedding the catalyst particles may anchor them within the substrate and inhibit them from migrating during fuel cell operation.

Fuel cell catalyst layers and methods of making the same are disclosed. The fuel cell catalyst layer may include a catalyst substrate including a non-woven mat of carbon nanofibers, each having a surface portion and a bulk portion bounded by the surface portion. A plurality of catalyst particles may be included in the catalyst layer, at least a first portion of which are fully embedded within the bulk portion of each of the carbon nanofibers. The method may include spinning a composition including a base polymer, a solvent, and a catalyst precursor into a non-woven fiber mat having the catalyst precursor embedded therein. The mat may then be carbonized to form a carbon fiber substrate and the catalyst precursor may be reacted to form catalyst particles embedded in the substrate. Embedding the catalyst particles may anchor them within the substrate and inhibit them from migrating during fuel cell operation.

A flexible all-solid state supercapacitor is provided that includes a first electrode and a second electrode, and a flexible nanofiber web, where the flexible nanofiber web connects the first electrode to the second electrode, where the flexible nanofiber web includes a plurality of flexible nanofibers, where the flexible nanofiber includes a hierarchal structure of macropores, mesopores and micropores through a cross section of the flexible nanofiber, where the mesopores and the micropores form a graded pore structure, where the macropores are periodically distributed along the flexible nanaofiber and within the graded pore structure.