Hydrophobic-treated yolk-shell SnS2@CSs Z-scheme confinement reactor for solar-electro-driven hydrogen peroxide production in neutral media.

This work combines the nanoconfined material with the air-breathing gas diffusion electrode equips a wide practical range of applications for the synthesis of high-yield H 2 O 2 and upgrading of H 2 O 2 products. [Display omitted] • Yolk-shell SnS 2 @CSs Z-scheme nanoreactor is controllably synthesized. • Hydrogen peroxide production is increased through the nano-confinement effect. • Continuous hydrophobic layers allow air to spontaneously diffuse into the AGPE. • The photoelectrode has a good reusability and stability for activation of O 2 /H 2 O. • Hydrogen peroxide is produced under neutral condition media. The diffusion and adsorption properties of the O 2 /H 2 O corpuscles at active sites play a crucial role in the fast photo-electrocatalytic reaction of hydrogen peroxide (H 2 O 2) production. Herein, SnS 2 nanosheets with abundant interfacial boundaries and large specific areas are encapsulated into hollow mesoporous carbon spheres (CSs) with flexibility, producing a yolk-shell SnS 2 @CSs Z-scheme photocatalyst. The nanoconfined microenvironment of SnS 2 @CSs could enrich O 2 /H 2 O in catalyst cavities, which allows sufficient internal O 2 transfer, improving the surface chemistry of catalytic O 2 to O 2 − conversion and increasing reaction kinetics. By shaping the mixture of SnS 2 @CSs and polytetrafluoroethylene (PTFE) on carbon felt (CF) using the vacuum filtration method, the natural air-breathing gas diffusion photoelectrode (AGPE) was prepared, and it can achieve an accumulated concentration of H 2 O 2 about 12 mM after a 10 h stability test from pure water at natural pH without using electrolyte and sacrificial agents. The H 2 O 2 product is upgraded through one downstream route of conversion of H 2 O 2 to sodium perborate. The improved H 2 O 2 production performance could be ascribed to the combination of the confinement effect of SnS 2 @CSs and the rich triple phase interfaces with the continuous hydrophobic layer and hydrophilic layer to synergistically modulate the photoelectron catalytic microenvironment, which enhanced the transfer of O 2 mass and offered a stronger affinity to oxygen bubbles. The strategy of combining the confined material with the air-breathing gas diffusion electrode equips a wide practical range of applications for the synthesis of high-yield hydrogen peroxide. [ABSTRACT FROM AUTHOR]