Monolithic Gyroidal Mesoporous Mixed Titanium–Niobium Nitrides

Abstract

Mesoporous transition metal nitrides are interesting materials for energy conversion and storage applications due to their conductivity and durability. We present ordered mixed titanium–niobium (8:2, 1:1) nitrides with gyroidal network structures synthesized from triblock terpolymer structure-directed mixed oxides. The materials retain both macroscopic integrity and mesoscale ordering despite heat treatment up to 600 °C, without a rigid carbon framework as a support. Furthermore, the gyroidal lattice parameters were varied by changing polymer molar mass. This synthesis strategy may prove useful in generating a variety of monolithic ordered mesoporous mixed oxides and nitrides for electrode and catalyst materials.

Block copolymer self-assembly–directed synthesis of mesoporous gyroidal superconductors

“…S1). A lower nitriding temperature of 600°C ( 18 ), or even 700°C, retained the mesostructure well, but the resulting materials were not superconducting. Numerous heating profiles were explored to strike a balance between superconductivity and the retention of an ordered mesoporous structure.…”

“…Peak broadening indicates some loss of the long-range order of the mesoscale structure. The corresponding lattice shrinkage is typical during the removal of organic materials and the condensation/crystallization of inorganic materials in block copolymer–oxide systems ( 18 ). After nitriding under ammonia first at 700°C and then at 850°/865°C, the SAXS patterns continue to shift to higher q values and to broaden ( Fig.…”

An Overview of Materials with Triply Periodic Minimal Surfaces and Related Geometry: From Biological Structures to Self‐Assembled Systems

“…This phase was later determined to be an alternating gyroid phase (Q 214 ), in which the A and C blocks form two chemically distinct, interpenetrating networks with opposite chirality, while B forms the TPMS (matrix) . This method has been widely employed because one block can be selectively etched to yield SG‐structured materials for optical applications (see Figure a) . Furthermore, the core–shell G structure was observed in 1999 by two independent groups .…”

Soft self-assembly of Weyl materials for light and sound

“…Directed self-assembly can induce mechanical strains in the direction of growth [115] which, according to our symmetry analysis, would automatically lead to the appearance of Weyl points without the need of applying external perturbations. Moreover, gyroid-based systems appear to be unusually resistant against the appearance of cracks when strained [116][117][118], possibly as a result of their three-dimensional co-continuous structure, making them a particularly good fit for our strain-based design. The size a of the unit cell of the structures obtained by block polymer self-assembly crucially depends on the blocks' molar mass.…”