Ternary CdS/Au/3DOM-SrTiO 3 composites with synergistic enhancement for hydrogen production from visible-light photocatalytic water splitting

Abstract

New ternary composites based on three dimensionally ordered macroporous (3DOM) SrTiO3 (CdS/Au/3DOM-SrTiO3) were prepared and used as photocatalysts in visible light (λ > 420 nm) photocatalytic water splitting for hydrogen evolution.Through optimizing the pore size of 3DOM-SrTiO3 materials and the loading amounts of Au and CdS, CdS/Au/3DOM-SrTiO3(300), templated by 300 nm sized poly(methyl methacrylate) colloids, was found to exhibit a remarkably enhanced photocatalytic hydrogen evolution rate (2.74 mmol/h•g), which was 3.2 times as high as that of CdS/Au/C-SrTiO3 catalyst based on commercial SrTiO3. This notably enhanced photocatalytic performance was mainly attributed to the slow photon enhancement effect of 3DOM-SrTiO3(300) material, which significantly promoted the light harvesting efficiency of ternary composite for the slow photon region of 3DOM-SrTiO3(300) was well matched with the optical absorption band of photocatalyst. Further depositing Pt nanoparticles on CdS/Au/3DOM-SrTiO3(300) composite as a co-catalyst, an extraordinarily high hydrogen evolution rate (up to 5.46 mmol/g•h) and apparent quantum efficiency (42.2% at 420 nm) were achieved because of the synergistic effect of efficient carrier separation, Au SPR effect, and slow photon effect. Furthermore, these ternary CdS/Au/3DOM-SrTiO3 composite photocatalysts were very stable and could be easily recycled four times in visible light photocatalytic water splitting experiments without any loss in activity.3 Keywords Three-dimensionally ordered macroporous material; CdS/Au/3DOM-SrTiO3; Ternary composite; Hydrogen production from water splitting; Slow photon effect.4

Hydrothermal synthesis of single-crystal Cr-doped SrTiO3 for efficient visible-light responsive photocatalytic hydrogen evolution

“…The crystallographic structure and phase composition of the as-prepared samples were detected by XRD. As shown in figure 1(a), the characteristic diffraction peaks at 22.78°, 32.42°, 39.98°, 46.48°, 57.79°and 67.80°c ould be indexed to the (100), (110), (111), (200), (211) and (220) planes of cubic SrTiO 3 (PDF#35-0734) [21]. Moreover, the XRD patterns shows quite a similar feature and the crystalline size was calculated via Scherrer formula.…”

Ionic liquid‐assisted synthesis of porous BiOBr microspheres with enhanced visible light photocatalytic performance

“…PL analysis of photocatalysts can be applied to reflect the transportation and recombination of the photoinduced electron–hole pairs. It is generally believed that a lower PL intensity is an indication of a lower recombination rate of photoinduced electron–hole pairs . The PL spectra of BiOBr‐IL‐1, BiOBr‐IL‐2 and BiOBr‐IL‐3 samples obtained with an excitation wavelength of 360 nm are shown in Figure .…”

Photocatalytic Hydrogen Evolution via Water Splitting: A Short Review

“…Therefore, the MoS 2 /gC 3 N 4 nanojunction significantly enhanced H 2 evolution efficiency, achieving the highest H 2 evolution rate and an optimum quantum efficiency of up to 2.1% (420 nm), which was higher than g-C 3 N 4 /Pt. H2 generation performance using g-C3N4 can be promoted with noble-metal particles such as Au or Pd, which obtain electrons in the CB to inhibit the charge recombination rate [86][87][88][89][90]. Many researchers are developing metal-free photocatalysts for H2 evolution, and recent reports involved the introduction of non-noble-metal catalysts into g-C3N4 photocatalysts, displaying enhanced photocatalytic performance compared to noble-metal catalysts [91][92][93][94][95].…”