Visible light-driven H₂O₂ synthesis over Au/C₃N₄: medium-sized Au nanoparticles exhibiting suitable built-in electric fields and inhibiting reverse H₂O₂ decomposition

Abstract

Visible light-driven H2O2 production presents unique merits of sustainability and environmental friendliness. The size of noble metal nano-particles (NPs) determines its dispersion and electronic structure, and greatly affects its photo-catalytic...

Enhanced Visible-Light H2O2 Production over Pt/g-C3N4 Schottky Junction Photocatalyst

“…On the other hand, the protons released by ethanol can take part in the oxygen reduction process, which speeds up the reaction of eq 3 and promotes the generation of H 2 O 2 . 23,53 It is worth mentioning that the yield of H 2 O 2 in the presence of ethanol over Pt0.05/g-C 3 N 4 reaches 520.7 μM in 1 h (or 2603.6 μmol•g −1 •h −1 ), which is also higher than most of those in the literature (see Table S1, most catalysts with higher noble-metal contents (>0.5 wt %)).…”

“…However, the low specific surface area, fast recombination of photogenerated carriers, and poor surface electron migration rate of single g-C 3 N 4 severely limit its applicability . To address these issues and improve its performance, various strategies such as introducing defects, element doping, , heterojunction engineering, , and noble-metal modification − have been investigated. Noble-metal modification was proved to be an effective strategy to improve the photocatalytic activity due to the high conductivity, low activation energy, and high work function of noble metals. − In particular, metal platinum (Pt) nanoparticles as a cocatalyst were deposited on the surface of g-C 3 N 4 to capture electrons to improve the separation efficiency of photocatalytic carriers and photocatalytic performance for H 2 O 2 production. , However, the contents of Pt in photocatalysts are generally higher than 0.5 wt % in the literature, − which severely limits its practical application owing to their low earth abundance and high price.…”

“…The smaller Pt nanoparticle size provides a larger surface area and a greater number of active sites. The Pt nanoparticles with different particle sizes will have different work functions and different Schottky barriers, 23,24,29 resulting in different charge transfer resistance. The inconsistent effect of noble metal particle size on photocatalytic performance was reported in the literature.…”

Synergy of oxygen vacancies and Bi nanoparticles on BiOBr nanosheets for enhanced photocatalytic H2O2 production

“…Thus, to maximize the H 2 O 2 generation efficiency of the photocatalyst system, it is essential to spur the surface catalytic reactions and inhibit the decomposition of H 2 O 2 . 20,21 Recently, the introduction of appropriate defects has been confirmed to be potential tactics to significantly improve the photocatalytic production of H 2 O 2 . 22,23 Oxygen vacancy is a fundamental and intrinsic defect in metal oxide semiconductors and has a critical effect on their electronic and physicochemical properties.…”

“…Thus, to maximize the H 2 O 2 generation efficiency of the photocatalyst system, it is essential to spur the surface catalytic reactions and inhibit the decomposition of H 2 O 2 . 20,21…”