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Title: A crystalline and 3D periodically ordered mesoporous quaternary semiconductor for photocatalytic hydrogen generation
We have prepared the first crystalline and 3D periodically ordered mesoporous quaternary semiconductor photocatalyst in an evaporation-induced self-assembly assisted soft-templating process. Using lab synthesized triblock-terpolymer poly(isoprene- b -styrene- b -ethylene oxide) (ISO) a highly ordered 3D interconnected alternating gyroid morphology was achieved exhibiting near and long-range order, as evidenced by small angle X-ray scattering (SAXS) and electron microscopy (TEM/SEM). Moreover, we reveal the formation process on the phase-pure construction of the material's pore-walls with its high crystallinity, which proceeds along a highly stable W 5+ compound, by both in situ and ex situ analyses, including X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR). The resulting photocatalyst CsTaWO 6 with its optimum balance between surface area and ordered mesoporosity ultimately shows superior hydrogen evolution rates over its non-ordered reference in photocatalytic hydrogen production. This work will help to advance new self-assembly preparation pathways towards multi-element multifunctional compounds for different applications, including improved battery and sensor electrode materials.  more » « less
Award ID(s):
1707836
PAR ID:
10059893
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
10
Issue:
7
ISSN:
2040-3364
Page Range / eLocation ID:
3225 to 3234
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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