MoS2 Nanoflowers as a Gateway for Solar-Driven CO2 Photoreduction

The layering of transition metal dichalcogenides (TMD) has revealed engineering opportunities for optoelectronics, field emitter, and photocatalysis applications. Precise and controlled intrinsic material property combinations is needed for visible light photocatalysis optimization, which we demonstrate in this work with MoS2 nanoflowers containing abundant edge plane flakes for CO2 photoreduction optimization. This is the first time controlled imperfections and flake thickness through facile chemical vapor deposition (CVD) synthesis were demonstrated on the nanoflowers, revealing the tuning ability of flake edge morphology, nanoflower size, stacked-sheet thickness, optical band gap energy (Eg), and catalytic function. These influences facilitated Eg tuning from 1.38 to 1.83 eV and the manifestation of the 3R phase prompting improvement to the catalytic behavior. The “sweet spot” of higher catalytic activity during photoreduction experiments was found in those with plentiful nanoflower density and thick e...

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