Hydrogen Evolution Over Heteropoly Blue-Sensitized Pt/TiO2 Under Visible Light Irradiation

We report the visible light-induced hydrogen generation over heteropoly blue (HPB) sensitized Pt/TiO₂ photocatalyst. HPB was obtained via UV-induced reduction of heteropoly acid K₅(BW₁₁O₃₉H₄) · 12.8H₂O (BW₁₁) in glycerol aqueous solution. The photocatalytic activity for hydrogen generation was found to be dependent on the concentration of HPB in the solution.     

Pt／K2La2Ti3O10催化剂的合成及可见光催化活性的研究

用高温固相法合成了具有类钙钛矿型结构的层状化合物K2La2TiO10用XRD、TEM、UV-DRS对其进行表征.利用不同还原方法制备了Pt/K2La2Ti3O10光催化剂.考察了在可见光下Pt/K2La2Ti3O10光催化制氢的活性.比较了负载Pt与负载Ni和纯的K2La2Ti3O10的光催化活性.研究了Pt负载量、不同还原方法对光催化分解水制氢反应的影响.在最佳的Pt负载量2%(Wt)下,产氢速率达到2.59 mol/m2·h.     

Mn2+掺杂ZnIn2S4多孔光催化剂催化产氢性能研究

以溴代十六烷基吡啶(CPBr)为模板剂,采用水热法制备出系列Mn2+掺杂的ZnIn2S4多孔光催化剂.通过XHD、FESEM、UV-Vis、XPS等分析手段对催化剂进行了表征,考察了掺杂Mn2+浓度对多孔ZnIn2S4光催剂的形貌结构和可见光催化产氢性能的影响.实验结果表明,Mn2+掺杂影响催化剂的晶体结构及其微观形貌...     

Mn0.3Cd0.7S Nanorods Modified by Amorphous FexP with Improved Photocatalytic Activity and Stability for H2 Evolution

Catalysis Letters - In this paper, a novel amorphous FexP was successfully synthesized and anchored onto the surface of Mn0.3Cd0.7S nanorods by a mild solvothermal technology. FexP/Mn0.3Cd0.7S-0.2...     

Controllable Synthesis of MoS<Subscript>2</Subscript>/h-CdS/c-CdS Nanocomposites with Enhanced Photocatalytic Hydrogen Evolution Under Visible Light Irradiation

Firstly, h-CdS/c-CdS homojunction was prepared by solvothermal method with controlling the Cd-to-S molar ratio. Then, the MoS₂/h-CdS/c-CdS nanocomposites were constructed by ultrasonic method with different MoS₂ amount. The experimental results showed that when the molar ratio of Cd and S was 1:1 and the amount of MoS₂ was 1.5 wt%, the MoS₂/h-CdS/c-CdS nanocomposites exhibited excellent photocatalytic performance for hydrogen evolution under visible light. The total amount of hydrogen evolution was 3753.12 µmol for 5 h, and its average hydrogen evolution rate was 40.79 mmol h^?1 g^?1 with an apparent quantum efficiency of 38.16% irradiated at 420 nm, which was about 7.3 times when compared with the h-CdS/c-CdS homojunction (Cd:S?=?1:8). The enhanced photocatalytic performance of MoS₂/h-CdS/c-CdS could be attributed to the improved specific surface area and formation of well bonded interface structure, which not only enhanced the response to visible light but also decreased the recombination rates of photogenerated charge carriers.

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糠醛、糠醇和糠酸为电子给体在Pt/TiO2上光催化制氢

糠醛、糠醇和糠酸在TiO2表面吸附符合Langmuir吸附模型,吸附常数分别为9.43×102、3.88×102和1.48×103L/mol。与纯水体系相比,4.00×10-3mol/L糠醛、糠醇和糠酸作电子给体时,10h光照Pt/TiO2光解水制氢效率分别提高了33.8、260和444。光照5h,糠醛、糠醇和糠酸分别降解了10.0,16.3和48.5,COD(化学需氧量)平均去除率分别为10.0、18.0和28.4mg/L.h。溶液pH对放氢有影响,糠醛和糠酸弱酸性条件下放氢效果好,而糠醇弱碱性条件下放氢效果好。通过对降解产物分析,探讨了污染物降解的可能反应机理。     

Photocatalytic Hydrogen Production from Aqueous Solutions of Alcohol as Model Compounds of Biomass Using Visible Light-Responsive TiO2 Thin Films

Visible light-responsive TiO₂ (Vis-TiO₂) thin films were prepared by a radio frequency magnetron sputtering deposition method. The photoelectrochemical performance was improved by adding various kinds and concentrations of alcohol, i.e., model compounds of biomass, to water. The separate evolution of pure H₂ was observed to proceed efficiently on these Vis-TiO₂ thin films under visible light irradiation by using an aqueous solution of methanol.     

Advanced Surface of Fibrous Activated Carbon Immobilized with FeO/TiO2 for Photocatalytic Evolution of Hydrogen under Visible Light

FeO-doped TiO₂ nanoparticle photocatalysts were immobilized onto the surface of fibrous activated carbon (ACF) via a sol-gel process. As an adsorbent and photocatalyst, FeO-TiO₂ on immobilized ACFs (FeO-TiO₂/ACF) greatly improved the photocatalysis rate of hydrogen production as compared with pure TiO₂ and ACF-TiO₂ under UV irradiation and visible light. The addition of ACFs surface significantly reduced the photogenerated pairs of electrons-hole recombination, thereby promoting the photocatalysis action of doped photo-metal oxides of FeO-TiO₂. Co-doping of FeO onto the lattice of the TiO₂ approach can improve the absorption activity of visible light through photo-metal oxide of TiO₂ and further enhance hydrogen production under visible light. The photocatalytic fabrics (FeO-TiO₂/ACF) were effortlessly split out from the experimental solution for re-utilization and exhibited high stability even after five complete regeneration cycles.     

Efficient H2 production on CoSx/Zn0.3Cd0.7S heterojunction by selective oxidation of p-chlorobenzyl alcohol in organic phase

Developing high-efficient photocatalysts for H₂ production is still the focus of current research. A series of CoS_x/Zn_0.3Cd_0.7S (CoS_x/ZCS) samples with different mass ratios were successfully synthesized for H₂ production by the oxidation of p-chlorobenzyl alcohol (Cl-PhCH₂OH). Herein, Zn_0.3Cd_0.7S (ZCS) solid-solution nanoparticles are distributed on the surface of CoS_x polyhedron, and CoS_x is obtained from ZIF-67, composed of Co_1−xS and CoS₂. The photocatalytic H₂ production was performed by Cl-PhCH₂OH oxidation in N,N-Dimethylformamide (DMF) solution under visible light irradiation, and 5% CoS_x/ZCS sample showed the best photocatalytic activity, with the H₂ generated rate high to 2.80 mmol g⁻¹ h⁻¹. Meanwhile, the selectivity of Cl-PhCH₂OH oxidation to p-chlorobenzaldehyde (Cl-PhCHO) is 97.6%, and the rate is 2.95 mmol g⁻¹ h⁻¹. Moreover, the reasons for the excellent photocatalytic performance of CoS_x/ZCS samples were deeply analyzed by experimental and theoretical results, such as trapping agents, photoelectrochemistry test, electron paramagnetic resonance (EPR), specific surface area, and density functional theory (DFT) calculation. This work provides a new theoretical guidance and experimental experience for the application of H₂ application and design of novel photocatalysts.     

A Facile One Step Synthesis of MoS2/g-C3N4 Photocatalyst with Enhanced Visible Light Photocatalytic Hydrogen Production

Catalysis Letters - Noble metal-free MoS2/g-C3N4 photocatalysts have been synthetized by one step thermal treatment of thiourea and sodium molybdate, which has intimate contact interfaces between...     

Thermal treatment effect on the magnetoelectric properties of (Ni0.5Zn0.5)Fe2O4/Pt/Pb(Zr0.3Ti0.7)O3 heterostructured thin films

Magnetoelectric (ME) property modulation in heterostructured (Ni_0.5Zn_0.5)Fe₂O₄/Pt/Pb(Zr_0.3Ti_0.7)O₃ (NZFO/Pt/PZT) thin films on platinized Si substrate by thermal annealing condition variation was studied. In an attempt to prevent interfacial reaction between NZFO and PZT layers during high temperature annealing, thin Pt layer was deposited which can serve as inter-diffusion barrier as well as electrode. The ferroelectric, magnetic, and ME properties of the heterostructured film were noticeably modulated due to microstructural evolution and clamping relaxation developed during thermal annealing process. Room temperature ME voltage coefficient of the heterostructured thin films was enhanced with increasing annealing temperature and reached to 29 mV/cm·Oe when annealed at 650 °C.     

TiO2/MS(M=Cd,Zn,Cu)纳米复合光催化剂的制备及光催化活性研究

在室温下,以正丁胺为模板剂[1],通过简单的化学方法合成ZnS,CdS,CuS纳米颗粒.以钛酸丁酯为主要原料,用溶胶-凝胶法制备了TiO2/ZnS,TiO2/CdS,TiO2/CuS的纳米复合物,采用UV-Vis对其进行简单表征.并通过测定甲基橙的脱色速率,评价所有样品的光催化活性.结果表明:不同的硫化物在同一复合量时...     

Hydrogen Production from Aqueous Solutions of Glycerol on TiO<Subscript>2</Subscript>/Ru-MCM-41 Photocatalysts Using Solar Light

Ru-MCM-41 molecular sieves were prepared (Si/Ru atomic ratio?=?50 or 100) by a hydrothermal method and impregnated with TiO₂. The materials were characterized by XRD, N₂ physisorption, DRS, SEM and TEM. Their potential application to hydrogen production by photolysis of water using solar light was tested in a batch reactor using mixtures of water and glycerol (0–6.85 mol L^?1) at pH varying from 1 to 11. The photocatalytic efficiency under simultaneous UV (0.05 μW cm^?2) and visible light (90.07 W m^?2) irradiation was compared to the activity of TiO₂/MCM-41 (i.e., no Ru incorporated) and commercial Degussa TiO₂ P25. The most active material was 20%TiO₂/Ru-MCM-41(100) whose performance (220.6 µmol g_Ti ^?1 H₂) was approximately 47 times higher than TiO₂ P25. Characterization results showed the deposition of TiO₂ and revealed the formation of RuO₂ on the surface. Hydrogen generation was improved due to higher charge separation at the TiO₂/RuO₂ heterojunction and to the enhancement of visible light absorption caused by surface plasmon resonance (SPR). Hydrogen production increased with glycerol concentration, tending to stabilize around 40.3 µmol h^?1 g_Ti ^?1 above 4 mol L^?1 of glycerol. Hydrogen generation reached its maximum at extreme values of pH (1 and 11).     

The Synthesis of (E)-Vinyl and Alkynyl Sulfones by the Formation of an Electron Donor-Acceptor Complex Using Thiosulfonates and Sodium Iodide Under Visible Light

A method for the synthesis of (E)-vinyl sulfones and alkynyl sulfones through the cleavage of thiosulfonate promoted by the formation of EDA complexes under visible light irradiation at room temperature without the need for other metal catalysts is described. The mechanism study shows that sodium iodide and thiosulfonate form EDA complexes under visible light irradiation, resulting in a single-electron transfer cleavage to generate sulfonyl radicals, which then react with olefins or alkynes to produce (E)-vinyl sulfones or alkynyl sulfones, respectively. This method is applicable to 44 olefin and alkyne substrates, with yields ranging from 38% to 90%, providing a radical synthesis approach for the preparation of sulfonylated compounds.     

Mesoporous V2O5/g-C3N4 Nanocomposites for Promoted Mercury (II) Ions Reduction Under Visible Light

Journal of Inorganic and Organometallic Polymers and Materials - The present study addresses a successful attempt to promote the photocatalytic reduction of mercury ions (Hg2+) over the synthesized...     

Modulation by 17,20S(OH)2pD of Fibrosis-Related Mediators in Dermal Fibroblast Lines from Healthy Donors and from Patients with Systemic Sclerosis

We previously demonstrated that the non-calcemic pregnacalciferol (pD) analog 17,20S (OH)₂pD suppressed TGF-β1-induced type I collagen production in cultured normal human dermal fibroblasts. In the present studies, we examined fibroblasts cultured from the lesional skin of patients with systemic sclerosis (scleroderma (SSc)) and assessed the effects of 17,20S(OH)₂pD on fibrosis-related mediators. Dermal fibroblast lines were established from skin biopsies from patients with SSc and healthy controls. Fibroblasts were cultured with either 17,20S(OH)₂pD or 1,25(OH)₂D₃ (positive control) with/without TGF-β1 stimulation and extracted for protein and/or mRNA for collagen synthesis and mediators of fibrosis (MMP-1, TIMP-1, PAI-1, BMP-7, PGES, GLI1, and GLI2). 1 7,20S(OH)₂pD (similar to 1,25(OH)₂D₃) significantly suppressed net total collagen production in TGF-β1-stimulated normal donor fibroblast cultures and in cultures of SSc dermal fibroblasts. 17,20S(OH)₂pD (similar to 1,25(OH)₂D₃) also increased MMP-1, BMP-7, and PGES and decreased TIMP-1 and PAI1 expression in SSc fibroblasts. Although 17,20S(OH)₂pD had no effect on Gli1 or Gli2 in SSc fibroblasts, it increased Gli2 expression when cultured with TGF-β1 in normal fibroblasts. These studies demonstrated that 17,20S(OH)₂pD modulates mediators of fibrosis to favor the reduction of fibrosis and may offer new noncalcemic secosteroidal therapeutic approaches for treating SSc and fibrosis.     

ZnIn2S4/g-C3N4 Nanocomposite for Proficient Elimination of Hg (II) under Visible Light

Journal of Inorganic and Organometallic Polymers and Materials - The present work offers beneficial method for Hg (II) elimination from aqueous solution. ZnIn2S4/g-C3N4 nanocomposites were...     

Photocatalytic Decomposition of Formic Acid Under Visible Light Irradiation Over V-ion-implanted TiO2 Thin Film Photocatalysts Prepared on Quartz Substrate by Ionized Cluster Beam (ICB) Deposition Method

Unique visible-light-responsive TiO₂ photocatalysts (λ>450 nm) were successfully developed by implantation of V ions into the TiO₂ thin films prepared on a quartz substrate by an ionized cluster beam (ICB) deposition method. After V ions implantation into TiO₂ thin film, the photocatalytic activity of the thin films for the decomposition of formic acid into CO₂ and H₂O was found to proceed efficiently under visible light irradiation longer than 450 nm. The TiO₂ thin film photocatalysts were characterized by XRD, UV-vis, XPS, FE-SEM and AFM.