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  • Accepted Manuscript: Integrating photocatalysis and thermocatalysis to enable efficient CO2 reforming of methane on Pt supported CeO2 with Zn doping and atomic layer deposited MgO overcoating
Title: Integrating photocatalysis and thermocatalysis to enable efficient CO2 reforming of methane on Pt supported CeO2 with Zn doping and atomic layer deposited MgO overcoating
CO2 reforming or dry reforming of methane (DRM) produces syngas with a low carbon footprint, but the efficiency and stability of DRM remains a challenge. Herein, we report an efficient photo-thermo-chemical DRM (PTC-DRM) process on a Pt supported CeO2 catalyst with Zn doping and surface atomic layer deposition (ALD)-enabled MgO overcoating using concentrated sunlight as the energy input. Under 30 suns irradiation at 600 °C, high syngas production rates of 356 and 516 mmol g−1 h−1 for H2 and CO are achieved, which are more than 9 and 3 times larger than those obtained in the thermally driven DRM. Moreover, the light illumination stabilizes the dry reforming process without deactivation, which results from the in situ generation of oxygen vacancy on CeO2 by photo-induced electrons that enables stable CO2 thermo-activation. The ALD coating also reduces surface charge recombination through passivating surface states, thereby enhancing photocatalytic activity.
Authors:
; ; ; ; ;
Award ID(s):
1924574
Publication Date:
NSF-PAR ID:
10158267
Journal Name:
Applied catalysis
Volume:
260
Page Range or eLocation-ID:
118189
ISSN:
0166-9834
Sponsoring Org:
National Science Foundation
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