Fig. 6: 3D printed BCP directed mesoporous superconductor (SC) properties.
From: Hierarchically ordered porous transition metal compounds from one-pot type 3D printing approaches
a Plot of magnetic moment normalized by mass (μ) of NbN-type samples treated to 550 °C in NH3 and higher temperatures in carburizing gas (inset: SEM micrograph of sample treated to 950 °C). b Plot of electrical resistance (R) of NbN-type sample treated to 500 °C in NH3 and then 950 °C in carburizing gas. c Plot of field-dependent R of sample in (a) treated to 950 °C (inset: variation of upper critical field (Bc2) with temperature (T) near Tc). d Plot of extrapolated Bc2 at T = 0 (Bc2(0), red) and corresponding Ginzburg–Landau coherence length (ξ(0), blue) as a function of room-temperature aging time (t, in days) in air for NbN-type sample treated to 575 °C in NH3 and then 950 °C in carburizing gas (error bars: extrapolation error, see Methods; inset: schematic of aging). e Plot of Bc2(0) for samples treated as in (c) as a function of Mn,PEO2/3, proportional to wall thickness, d (top axis). For a given Mn,PEO, lighter blue points represent results from separate samples, while the dark blue point represents the average (error bars: standard deviation). The green point represents a hexagonally ordered sample derived from a tailor-made PI-b-PS-b-PEO. The teal line indicates the Bc2(0) value for bulk NbN averaged from refs. 26,33,34. The dotted pink and red lines represent Bc2(0) values of NbN in confined geometries from ref. 36. and ref. 37, respectively. The inset shows a plot of Bc2(0) values (error bars: extrapolation error, see Methods) for F127-directed TiN samples (Supplementary Fig. 22) against the dotted green line, which indicates the Bc2(0) value reported for TiN under confinement from ref. 43.
