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Title: Optical Properties and Photocatalytic Performance of Si/TiO 2 Tandem Semiconductor Microwire Slurries
Semiconductor particle suspension reactors hold promise as a possible low-cost strategy for solar water-splitting, but they face several challenges that have inhibited their solar-to hydrogen (STH) efficiencies. A tandem microparticle with a buried junction addresses some of these challenges and offers a pathway to high STH efficiency. As a slurry, the tandem microparticles need to be suspended and well dispersed with maximum light absorption for a minimal photoactive particle concentration. Herein, proof-of-concept Ni/np+-Si/FTO/TiO2 tandem microwire structures capable of unassisted solar water-splitting were investigated as a slurry using uplifting N2 carrier gas bubbles. Transmittance, reflectance, and absorptance of the slurry were characterized as a function of wavelength, bubble flowrate, and tandem microwire concentration using an integrating sphere. Notably, a slurry absorptance of 70−85% was achieved with only 1% of the solution volume filled with a photoactive material. Photochemical activity of the slurry was characterized with in situ monitoring of the photodegradation of methylene blue, including the effects of particle concentration, bubble flowrate, spectral mismatch, intermixed light scattering particles, and a back reflector.  more » « less
Award ID(s):
1943977
PAR ID:
10494061
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACS Energy & Fuels
Date Published:
Journal Name:
Energy & Fuels
Volume:
37
Issue:
12
ISSN:
0887-0624
Page Range / eLocation ID:
8573 to 8582
Subject(s) / Keyword(s):
slurry solar fuel tandem microwire photocatalysis water-splitting
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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