Photocatalytic Hydrogen Production from Aqueous Solutions of Glucose and Xylose over Layered Perovskite-like Oxides HCa2Nb3O10, H2La2Ti3O10 and Their Inorganic-Organic Derivatives (original) (raw)
Related papers
Renewable and Sustainable Energy Reviews, 2020
Photocatalytic hydrogen production via water splitting is one of the favorable technologies for the solar energy conversion to renewable and sustainable energy; however, semiconductor materials under consideration have lower efficiency, selectivity and stability. Recently, perovskites are most demanding semiconductor photocatalysts belonging to very important family of materials and exhibit exceptional visible light response towards photocatalytic application. This review highlights recent developments in perovskite materials and their modification approaches for improved photocatalytic H 2 production. Primarily, the classification of perovskites based on structural developments; in particular, thermodynamics engineering to minimize energy barriers are discussed. Different approaches for fabrication of perovskite materials by metal and non-metal doping, while focusing on mechanism of Schottky barrier and Surface Plasmon phenomenon to improve photocatalytic efficiency are explored. This review also presents band engineering approaches in perovskites such as site substitution, solid-solution formation and nitrification of perovskites to maximize H 2 evolution. Elaboration of layered perovskite and improvement in their efficiency by various fabrication techniques including Z-scheme formation and composite of perovskite with TiO 2 and carbon-based composites including g-C 3 N 4 and rGO in terms of multicomponent heterojunction based on transfer of electron-hole pairs are critically deliberated. Finally, future perspectives of perovskite materials and their efficiency enhancement approaches for sustainable solar to hydrogen production has been suggested.
Catalysts, 2021
A series of hybrid inorganic–organic niobates HCa2Nb3O10×ROH, containing n-alkoxy groups of primary alcohols (R = Me, Et, Pr, Bu, Hx, and Dc) grafted in the interlayer space, has been studied for the first time in relation to photocatalytic hydrogen generation from a model 1 mol % aqueous solution of methanol under ultraviolet irradiation. Photocatalytic activity was measured both for bare samples and for their composites with Pt nanoparticles as a cocatalyst. The advanced measurement scheme allowed monitoring the volume concentration of a sample in a suspension during the experiment, its pH, and possible exfoliation of layered compounds into nanolayers. In the series of n-alkoxy derivatives, the maximum rate of hydrogen evolution was achieved over a Pt-loaded ethoxy derivative HCa2Nb3O10×EtOH/Pt. Its apparent quantum efficiency of 20.6% in the 220–350 nm range was found not to be caused by changes in the light absorption region or specific surface area upon ethanol grafting. Moreov...
Frontiers in Chemistry, 2020
A series of hybrid niobates HCa 2 Nb 3 O 10 ×RNH 2 , containing n-alkylamines (R = Me, Et, Pr, Bu, Hx, Oc) intercalated into the interlayer space, has been thoroughly studied concerning the photocatalytic hydrogen production from a model aqueous solution of methanol for the first time. All the hybrid photocatalysts were synthesized by the conventional ceramic technique followed by protonation and intercalation of nalkylamines. The products were characterized using XRD, Raman, IR and diffuse reflectance spectroscopy, TGA, CHN-analysis and SEM. Photocatalytic measurements were conducted according to an advanced scheme taking into account possible changes in the photocatalyst concentration because of sedimentation, pH shifts and exfoliation of the samples into nanoplatelets. Special attention was also paid to the feasible improvement of the photocatalytic activity of the samples via their modification with Pt nanoparticles as a cocatalyst. In the series of amine derivatives, the highest rate of hydrogen generation was demonstrated by the Pt-loaded HCa 2 Nb 3 O 10 ×BuNH 2 reaching apparent quantum efficiency of 13% in the 220-340 nm range. The initial HCa 2 Nb 3 O 10 showed comparable efficiency of 8.3% that is greater than for other amine derivatives. It was demonstrated that for the investigated samples the photocatalytic activity correlates with their ability of water intercalation.
Catalysts, 2021
Two series of hybrid inorganic-organic derivatives, obtained via the modification of protonated Ruddlesden–Popper phases H2Ln2Ti3O10 (Ln = La, Nd) with intercalated n-alkylamines and grafted n-alkoxy groups, have been systematically investigated in relation to photocatalytic hydrogen production from a model of 1 mol % aqueous solution of methanol for the first time. Photocatalytic measurements were performed both for bare samples and for their composites with Pt nanoparticles as a cocatalyst using an advanced scheme, including dark stages, monitoring of the volume concentration of the sample in the reaction suspension during the experiment, shifts of its pH and possible exfoliation of layered compounds into nanolayers. It was found that the incorporation of organic components into the interlayer space of the titanates increases their photocatalytic activity up to 117 times compared with that of the initial compounds. Additional platinization of the hybrid samples’ surface allowed fo...
Photocatalytic Conversion of Glucose to H2 over Lafeo3 Perovskite Nanoparticles
Chemical engineering transactions, 2016
The aim of this work was to evaluate the influence of operating conditions in the photocatalytic hydrogen production from glucose solution on LaFeO 3 nanoparticles under UV and visible through light-emitting diodes (LEDs). In particular, LaFeO 3 prepared by solution combustion synthesis with a specific amount of citric acid used as fuel, has been tested. The process efficiency was evaluated in terms of both glucose degradation and hydrogen production during the irradiation time. The influence of initial glucose concentration, catalyst dosage, and light source has been evaluated. Experimental results showed that the initial concentration of glucose affected the photocatalytic hydrogen production, and in particular the hydrogen production increased linearly (up to 370 µmol) as glucose concentration was increased up to 1000 mg L-1. Moreover, 1.5 g L-1 was found to be the optimum value for the catalysts dosage for obtaining the best photocatalytic hydrogen production after 4 h of irradiation. Furthermore, LaFeO 3 nanoparticles were active in the production of hydrogen also under visible light.
Materials
This review paper focuses on perovskite-type materials as (photo)catalysts for energy and environmental applications. After a short introduction and the description of the structure of inorganic and hybrid organic-inorganic perovskites, the methods of preparation of inorganic perovskites both as powders via chemical routes and as thin films via laser-based techniques are tackled with, for the first, an analysis of the influence of the preparation method on the specific surface area of the material obtained. Then, the (photo)catalytic applications of the perovskites in energy production either in the form of hydrogen via water photodecomposition or by methane combustion, and in the removal of organic pollutants from waste waters, are reviewed.
1981
The oxidation of Hz and CO was studied over LaCoOl, SrTiOs, BaTiOS, and related materials such as Ba(Feo.ssTio.s,)Ot.s, ZnO, and TiOx in the dark and while being irradiated with band-gap light. No effect of light on the rate of H, oxidation was found with any of these materials, but a strong photocatalytic effect was observed for CO oxidation over TiOL, ZnO, SrTiOl, and BaTiOs. In addition, a very similar behavior related to the ferroelectric properties of the catalyst was observed for CO oxidation, and less clearly for HP oxidation, over BaTiOa in the dark. The effect of light is discussed in terms of band-to-band transitions followed by hole capture, whereas the influence of ferroelectricity is thought to arise from the effect of polarized surface layers on the shape of the energy bands.
Frontiers in Chemistry, 2019
A layered perovskite-type oxide intercalated with n-butylamine is reported as an efficient photocatalyst for hydrogen production from aqueous solutions of alcohols for the first time. The hybrid photocatalyst H 2 Nd 2 Ti 3 O 10 ×BuNH 2 was synthesized by solid-state ceramic method followed by protonation, intercalation of methylamine and subsequent substitution by n-butylamine. The product was characterized by powder XRD, TGA, STA-MS, DRS, IR, and Raman spectroscopy, CHN analysis, SEM. Intercalation of n-butylamine caused a dramatic increase in photocatalytic activity of H 2 Nd 2 Ti 3 O 10 in the reaction of hydrogen evolution from aqueous solutions of methanol, ethanol, and n-butanol under UV radiation. While the non-intercalated Pt-loaded H 2 Nd 2 Ti 3 O 10 showed a maximum quantum efficiency of only 2% in the 220-340 nm range, the efficiency for hybrid samples reached 23% under the same conditions and after variation of experimental parameters even 52% efficiency was achieved. This effect may be associated with the significant expansion of the interlayer space, which is considered as a separate reaction zone.