Pub Date : 2025-01-03DOI: 10.1016/j.cattod.2025.115184
K. Jori , M. Mizrahi , L.J. Giovanetti , J.M. Ramallo-López , D. Buceta , I.R. Arias , J.M. Blanco Trillo , M.A.López Quintela , F.G. Requejo
To produce an impact in the reduction of sulfur derivatives on the environment it is essential to further eliminate the sulfur content in fuels. Although oxidative desulfurization using low temperatures and atmospheric pressure is a very appealing alternative to the currently used, and highly energy demanding, hydrodesulfurization method, it suffers from the use of high amounts of oxidizing agents such as NO2, H2O2, and tert-butyl-hydro-peroxide, especially for the oxidation of highly oxidation-resistant compounds as thiophens. Using X-ray absorption near edge structure (XANES) spectroscopy, we show that Ag clusters of 5 atoms (Ag5) have high catalytic activities to achieve the complete oxidation (S−2 to S+6) of highly oxidation-resistant compounds, such as dibenzothiophene, tetraphenyl thiophene and asphaltene, under ambient conditions in a simple and efficient process. Additionally, an analysis regarding the effect of Ag5 concentration for possible oxidation routes for dibenzothiophene is shown. These results can open a new avenue to face the challenge of reducing the presence of sulfur compounds in fuels using simple and green approaches.
{"title":"Room temperature aerobic oxidation of thiophenes catalyzed by silver 5-atoms clusters","authors":"K. Jori , M. Mizrahi , L.J. Giovanetti , J.M. Ramallo-López , D. Buceta , I.R. Arias , J.M. Blanco Trillo , M.A.López Quintela , F.G. Requejo","doi":"10.1016/j.cattod.2025.115184","DOIUrl":"10.1016/j.cattod.2025.115184","url":null,"abstract":"<div><div>To produce an impact in the reduction of sulfur derivatives on the environment it is essential to further eliminate the sulfur content in fuels. Although oxidative desulfurization using low temperatures and atmospheric pressure is a very appealing alternative to the currently used, and highly energy demanding, hydrodesulfurization method, it suffers from the use of high amounts of oxidizing agents such as NO<sub>2</sub>, H<sub>2</sub>O<sub>2</sub>, and tert-butyl-hydro-peroxide, especially for the oxidation of highly oxidation-resistant compounds as thiophens. Using X-ray absorption near edge structure (XANES) spectroscopy, we show that Ag clusters of 5 atoms (Ag5) have high catalytic activities to achieve the complete oxidation (S<sup>−2</sup> to S<sup>+6</sup>) of highly oxidation-resistant compounds, such as dibenzothiophene, tetraphenyl thiophene and asphaltene, under ambient conditions in a simple and efficient process. Additionally, an analysis regarding the effect of Ag5 concentration for possible oxidation routes for dibenzothiophene is shown. These results can open a new avenue to face the challenge of reducing the presence of sulfur compounds in fuels using simple and green approaches.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"449 ","pages":"Article 115184"},"PeriodicalIF":5.2,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-03DOI: 10.1016/j.cattod.2025.115183
Jianbo Wang , Jianteng Yan , Qingyan Cui , Tiesen Li , Jie Shi , Tinghai Wang , Yuanyuan Yue , Xiaojun Bao
In order to gain insight into the influence of SiO2 support particle size on the vacuum residue (VR) slurry-phase hydrocracking performance of Fe-based catalysts, a series of FeZn/SiO2 catalysts with varying SiO2 particle sizes were prepared. Characterization results show that the surface area and pore volume of the FeZn/SiO2 catalysts increase with the reduction of SiO2 particle sizes. The metals Fe and Zn species on FeZn/SiO2-S catalyst are more readily reducible via H2-TPR analysis. Notably, FeZn/SiO2-S catalyst presents higher metal dispersion and a greater degree of sulfurization compared to the other catalysts by XRD and XPS. Hydrocracking results demonstrate that the FeZn/SiO2-S catalyst achieves the lowest coke and gas yields (11.9 wt% and 0.4 wt%), respectively, and the highest VR conversion among these catalysts. The superior performance of the FeZn/SiO2-S catalyst in VR slurry-phase hydrocracking is ascribed to its enhanced hydrogenation activity, deriving from the higher dispersion and sulfurization of metals species. This suppresses the aggregation of polycyclic aromatic hydrocarbons in VR and the over-cracking of intermediate products. Additionally, the increased mesopore associated with smaller SiO2 particles facilitates to the diffusion of large VR molecules, further promoting the hydrocracking reaction.
{"title":"Effect of SiO2 support particle sizes on the performance of FeZn catalysts in VR slurry-phase hydrocracking","authors":"Jianbo Wang , Jianteng Yan , Qingyan Cui , Tiesen Li , Jie Shi , Tinghai Wang , Yuanyuan Yue , Xiaojun Bao","doi":"10.1016/j.cattod.2025.115183","DOIUrl":"10.1016/j.cattod.2025.115183","url":null,"abstract":"<div><div>In order to gain insight into the influence of SiO<sub>2</sub> support particle size on the vacuum residue (VR) slurry-phase hydrocracking performance of Fe-based catalysts, a series of FeZn/SiO<sub>2</sub> catalysts with varying SiO<sub>2</sub> particle sizes were prepared. Characterization results show that the surface area and pore volume of the FeZn/SiO<sub>2</sub> catalysts increase with the reduction of SiO<sub>2</sub> particle sizes. The metals Fe and Zn species on FeZn/SiO<sub>2</sub>-S catalyst are more readily reducible via H<sub>2</sub>-TPR analysis. Notably, FeZn/SiO<sub>2</sub>-S catalyst presents higher metal dispersion and a greater degree of sulfurization compared to the other catalysts by XRD and XPS. Hydrocracking results demonstrate that the FeZn/SiO<sub>2</sub>-S catalyst achieves the lowest coke and gas yields (11.9 wt% and 0.4 wt%), respectively, and the highest VR conversion among these catalysts. The superior performance of the FeZn/SiO<sub>2</sub>-S catalyst in VR slurry-phase hydrocracking is ascribed to its enhanced hydrogenation activity, deriving from the higher dispersion and sulfurization of metals species. This suppresses the aggregation of polycyclic aromatic hydrocarbons in VR and the over-cracking of intermediate products. Additionally, the increased mesopore associated with smaller SiO<sub>2</sub> particles facilitates to the diffusion of large VR molecules, further promoting the hydrocracking reaction.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"449 ","pages":"Article 115183"},"PeriodicalIF":5.2,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The photothermo-catalysis is a combined multicatalytic approach that allows to overcome some drawbacks of the respective single catalytic processes as the thermocatalysis and the photocatalysis. In this work, to efficiently exploit the potentiality of the solar photothermo-catalysis, SiC/hydrotalcites-derived catalysts were prepared with a simple hydrothermal method to exploit both the thermocatalytic properties of the formed multifunctional mixed oxides and the photo(thermo)-catalytic features of the silicon carbide. Two different hydrotalcite-derived catalysts were prepared, one with Mg-Co ions and another with Zn-Co ions. This latter sample, after the addition of SiC, showed the best performance in the CO2 methanation reaction, with a CH4 selectivity maximum of 71 % in the photothermal conditions at 250 °C, strongly improving the performance of the thermocatalysis (36 % at 350 °C). The presence of SiC permitted to increase the harvesting of the solar light, to modify the basic sites of the hydrotalcite-derived catalysts, allowing an efficient CO2 activation, and to generate self-heating effects that enhanced the photo-driven thermocatalysis. Moreover, the formation of photocatalytic active species as the ZnO and the ZnAl2O4 after the calcination of the corresponding hydrotalcite precursor, led to exploit additional photocatalytic contributions to further increase the catalytic activity in the photo-promoted thermocatalytic CO2 conversion into methane. The high versatility and the several synergisms generated by the application of this hybrid catalysis with these peculiar SiC/hydrotalcite-derived catalysts can be a sustainable strategy to efficiently valorise the carbon dioxide.
{"title":"Solar-promoted photo-thermal CO2 methanation on SiC/hydrotalcites-derived catalysts","authors":"Roberto Fiorenza , Luca Calantropo , Eleonora La Greca , Leonarda Francesca Liotta , Antonino Gulino , Angelo Ferlazzo , Maria Grazia Musumeci , Giuseppe Proietto Salanitri , Sabrina Carola Carroccio , Giusy Dativo , Maria Teresa Armeli Iapichino , Salvatore Scirè , Giuliana Impellizzeri","doi":"10.1016/j.cattod.2024.115182","DOIUrl":"10.1016/j.cattod.2024.115182","url":null,"abstract":"<div><div>The photothermo-catalysis is a combined multicatalytic approach that allows to overcome some drawbacks of the respective single catalytic processes as the thermocatalysis and the photocatalysis. In this work, to efficiently exploit the potentiality of the solar photothermo-catalysis, SiC/hydrotalcites-derived catalysts were prepared with a simple hydrothermal method to exploit both the thermocatalytic properties of the formed multifunctional mixed oxides and the photo(thermo)-catalytic features of the silicon carbide. Two different hydrotalcite-derived catalysts were prepared, one with Mg-Co ions and another with Zn-Co ions. This latter sample, after the addition of SiC, showed the best performance in the CO<sub>2</sub> methanation reaction, with a CH<sub>4</sub> selectivity maximum of 71 % in the photothermal conditions at 250 °C, strongly improving the performance of the thermocatalysis (36 % at 350 °C). The presence of SiC permitted to increase the harvesting of the solar light, to modify the basic sites of the hydrotalcite-derived catalysts, allowing an efficient CO<sub>2</sub> activation, and to generate self-heating effects that enhanced the photo-driven thermocatalysis. Moreover, the formation of photocatalytic active species as the ZnO and the ZnAl<sub>2</sub>O<sub>4</sub> after the calcination of the corresponding hydrotalcite precursor, led to exploit additional photocatalytic contributions to further increase the catalytic activity in the photo-promoted thermocatalytic CO<sub>2</sub> conversion into methane. The high versatility and the several synergisms generated by the application of this hybrid catalysis with these peculiar SiC/hydrotalcite-derived catalysts can be a sustainable strategy to efficiently valorise the carbon dioxide.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"449 ","pages":"Article 115182"},"PeriodicalIF":5.2,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new magnetically recoverable polypyrrole supported copper based nanocatalyst was synthesized, characterized with various analytical techniques like Fourier-transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray analysis (EDX), High Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric analysis (TGA), Vibrating Sample Magnetometry (VSM), and Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. The loading of copper on the surface of the catalyst was found to be 4.23 wt%. The application of the synthesized nanocatalyst was checked for the N-arylation of imidazoles. Excellent catalytic performance was obtained with easy recoverability and reusability upto six cycles. The current green protocol makes it environmentally beneficial for scale-up industries.
{"title":"Nano-architectured polypyrrole based magnetic nanocatalyst for the N- arylation of imidazoles and fused imidazoles","authors":"Sumanth Hegde, Sajin Surendran, Ajesh Vijayan, Aatika Nizam","doi":"10.1016/j.cattod.2024.115180","DOIUrl":"10.1016/j.cattod.2024.115180","url":null,"abstract":"<div><div>A new magnetically recoverable polypyrrole supported copper based nanocatalyst was synthesized, characterized with various analytical techniques like Fourier-transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray analysis (EDX), High Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric analysis (TGA), Vibrating Sample Magnetometry (VSM), and Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. The loading of copper on the surface of the catalyst was found to be 4.23 wt%. The application of the synthesized nanocatalyst was checked for the <em>N-</em>arylation of imidazoles. Excellent catalytic performance was obtained with easy recoverability and reusability upto six cycles. The current green protocol makes it environmentally beneficial for scale-up industries.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"449 ","pages":"Article 115180"},"PeriodicalIF":5.2,"publicationDate":"2024-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-27DOI: 10.1016/j.cattod.2024.115179
Rachelle M. Choueiri , Stephen W. Tatarchuk , Olivia G. Parker, William M. Cooper, Leanne D. Chen
The ammonia oxidation reaction (AOR) is a reaction of great interest for its potential to upcycle ammonia waste, creating fertilizer salts beneficial for the agricultural industry. Currently, AOR catalysts typically suffer either from high onset potentials or catalyst poisoning, and better catalyst materials must be found in order for AOR to be viable for large-scale fertilizer production. Experimentally, it is difficult to study the interactions of adsorbates on catalyst surfaces on an atomic level, whereas computational studies provide us with a means to study catalysts on this scale. In this study, we use density functional theory (DFT) calculations to develop linear scaling relations for ammonia oxidation using a set of ten reference metals. The scaling relations were used in a microkinetic model to predict the most active transition metal electrocatalysts for the AOR.
{"title":"Scaling relations for ammonia oxidation","authors":"Rachelle M. Choueiri , Stephen W. Tatarchuk , Olivia G. Parker, William M. Cooper, Leanne D. Chen","doi":"10.1016/j.cattod.2024.115179","DOIUrl":"10.1016/j.cattod.2024.115179","url":null,"abstract":"<div><div>The ammonia oxidation reaction (AOR) is a reaction of great interest for its potential to upcycle ammonia waste, creating fertilizer salts beneficial for the agricultural industry. Currently, AOR catalysts typically suffer either from high onset potentials or catalyst poisoning, and better catalyst materials must be found in order for AOR to be viable for large-scale fertilizer production. Experimentally, it is difficult to study the interactions of adsorbates on catalyst surfaces on an atomic level, whereas computational studies provide us with a means to study catalysts on this scale. In this study, we use density functional theory (DFT) calculations to develop linear scaling relations for ammonia oxidation using a set of ten reference metals. The scaling relations were used in a microkinetic model to predict the most active transition metal electrocatalysts for the AOR.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115179"},"PeriodicalIF":5.2,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-20DOI: 10.1016/j.cattod.2024.115167
Vanessa S.S. Favacho , Dulce M.A. Melo , Jennifer E.L. Costa , Lalyson M.L.R. Souza , Yuri K.R.O. Silva , Amanda L. Azevedo , Ângelo A.S. Oliveira , Renata M. Braga , Rodolfo L.B.A. Medeiros
LaNiO₃ perovskite catalytic precursors synthesized via the hydrothermal method can exhibit different structures and morphologies depending on the synthesis factors, such as soft templates and pH. Depending on the structures and morphologies of the catalytic precursors, their catalytic performance (field, conversion, stability, etc.) in dry reforming of methane (DRM) may change. Thus, this study aimed to synthesize LaNiO3 catalytic precursors with rod-like morphology by the hydrothermal method without and with soft templates (CTAB and citric acid), varying pH values (9 and 13), to evaluate the best catalytic precursors in DRM. The samples were characterized by energy-dispersive X-ray spectroscopy (EDXRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption-desorption analysis, H2 temperature-programmed reduction (H2-TPR), and thermogravimetric analyses (TGA/DTG/DTA). After activation, the catalysts' performance was evaluated based on a stability test in DRM for 15 h at 600 °C and with 96 L h−1 g−1 GHSV (gas hourly space velocity). Thus, the results showed that the LaNiO3 catalytic precursors synthesized without soft template at pH 9 and 13 presented rod-like morphology and were chosen for DRM application. The reducibility test showed that the catalysts synthesized at pH 9 and 13 had a degree of reduction of 69.89 % and 77.18 %, respectively. The stability test showed that the catalyst synthesized at pH 13 had a greater CH4 and CO2 conversion and stability than the catalyst synthesized at pH 9, as well as the H2 and CO yield, and H2/CO ratio. Its greater stability was assigned to its nanorod-like morphology, which favored a more homogeneous Ni0 dispersion after activation stage. Furthermore, the spent catalysts showed whisker-like carbon deposition, in which the catalyst synthesized at pH 13 (90.36 wt%) had a greater amount than the catalyst synthesized at pH 9 (47.67 wt%). Its greater whisker-like carbon deposition was assigned to the lower amount of La2O2CO3 phase formed after DRM.
{"title":"Influence of pH and soft templates on the hydrothermal synthesis of rod-shaped LaNiO3 catalytic precursors applied to dry reforming of methane for hydrogen production","authors":"Vanessa S.S. Favacho , Dulce M.A. Melo , Jennifer E.L. Costa , Lalyson M.L.R. Souza , Yuri K.R.O. Silva , Amanda L. Azevedo , Ângelo A.S. Oliveira , Renata M. Braga , Rodolfo L.B.A. Medeiros","doi":"10.1016/j.cattod.2024.115167","DOIUrl":"10.1016/j.cattod.2024.115167","url":null,"abstract":"<div><div>LaNiO₃ perovskite catalytic precursors synthesized via the hydrothermal method can exhibit different structures and morphologies depending on the synthesis factors, such as soft templates and pH. Depending on the structures and morphologies of the catalytic precursors, their catalytic performance (field, conversion, stability, etc.) in dry reforming of methane (DRM) may change. Thus, this study aimed to synthesize LaNiO<sub>3</sub> catalytic precursors with rod-like morphology by the hydrothermal method without and with soft templates (CTAB and citric acid), varying pH values (9 and 13), to evaluate the best catalytic precursors in DRM. The samples were characterized by energy-dispersive X-ray spectroscopy (EDXRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), N<sub>2</sub> adsorption-desorption analysis, H<sub>2</sub> temperature-programmed reduction (H<sub>2</sub>-TPR), and thermogravimetric analyses (TGA/DTG/DTA). After activation, the catalysts' performance was evaluated based on a stability test in DRM for 15 h at 600 °C and with 96 L h<sup>−1</sup> g<sup>−1</sup> GHSV (gas hourly space velocity). Thus, the results showed that the LaNiO<sub>3</sub> catalytic precursors synthesized without soft template at pH 9 and 13 presented rod-like morphology and were chosen for DRM application. The reducibility test showed that the catalysts synthesized at pH 9 and 13 had a degree of reduction of 69.89 % and 77.18 %, respectively. The stability test showed that the catalyst synthesized at pH 13 had a greater CH<sub>4</sub> and CO<sub>2</sub> conversion and stability than the catalyst synthesized at pH 9, as well as the H<sub>2</sub> and CO yield, and H<sub>2</sub>/CO ratio. Its greater stability was assigned to its nanorod-like morphology, which favored a more homogeneous Ni<sup>0</sup> dispersion after activation stage. Furthermore, the spent catalysts showed whisker-like carbon deposition, in which the catalyst synthesized at pH 13 (90.36 wt%) had a greater amount than the catalyst synthesized at pH 9 (47.67 wt%). Its greater whisker-like carbon deposition was assigned to the lower amount of La<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> phase formed after DRM.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115167"},"PeriodicalIF":5.2,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143150020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-20DOI: 10.1016/j.cattod.2024.115171
Wiktoria Adamowicz , Marcin Kobielusz , Paweł Mikrut , Wojciech Macyk
This work elucidates the influence of exposed facets of anatase-TiO2 crystals on the efficiency and selectivity of reduction of functionalised nitrobenzene derivatives. Titanium dioxide crystals in the form of bipyramids, sheets, and belts offering different exposed facets {001}/{101}, {001}, and {100}, respectively, were synthesised. Electrochemical analysis revealed a slight positive shift in the reduction potential of belt TiO2. The highest photocurrents were observed for sheets, whereas in the presence of methanol, the photocurrent doubling effect was observed for belts and bipyramids, with the most efficient methanol oxidation in the case of belts. The highest reaction rate constant for the reduction of 3-nitrophenol and 1-iodo-4-nitrobenzene was also noticed for belts. The observed differences in the resulting photocatalytic activity of nitroaromatics reduction were attributed to different efficiencies of methanol oxidation taking place at the tested photocatalysts.
{"title":"Photocatalytic reduction of nitroaromatic compounds over tailored anatase TiO2 crystals","authors":"Wiktoria Adamowicz , Marcin Kobielusz , Paweł Mikrut , Wojciech Macyk","doi":"10.1016/j.cattod.2024.115171","DOIUrl":"10.1016/j.cattod.2024.115171","url":null,"abstract":"<div><div>This work elucidates the influence of exposed facets of anatase-TiO<sub>2</sub> crystals on the efficiency and selectivity of reduction of functionalised nitrobenzene derivatives. Titanium dioxide crystals in the form of bipyramids, sheets, and belts offering different exposed facets {001}/{101}, {001}, and {100}, respectively, were synthesised. Electrochemical analysis revealed a slight positive shift in the reduction potential of belt TiO<sub>2</sub>. The highest photocurrents were observed for sheets, whereas in the presence of methanol, the photocurrent doubling effect was observed for belts and bipyramids, with the most efficient methanol oxidation in the case of belts. The highest reaction rate constant for the reduction of 3-nitrophenol and 1-iodo-4-nitrobenzene was also noticed for belts. The observed differences in the resulting photocatalytic activity of nitroaromatics reduction were attributed to different efficiencies of methanol oxidation taking place at the tested photocatalysts.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115171"},"PeriodicalIF":5.2,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143150013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-19DOI: 10.1016/j.cattod.2024.115168
Sandra Yurani Toledo Camacho , Francisco Mediana Cabello , Sandra Contreras Iglesias , Philip R. Davies , David J. Morgan , Auttaphon Chachvalvutikul
Layered Double-Hydroxides (LDH) materials are promising catalysts for solar-driven reactions thanks to their two-dimensional and the tunability of their composition. The preparation of three bimetallic NiFe-, NiCo- and ZnAl-LDH for H2 production by the photoreforming of glycerol under UV and visible irradiation has been investigated. Different modifications were studied: calcination, thermal reduction, plus Pt loading and TiO2 doping. Samples exhibited typical features of LDHs in XRD and hexagonal crystallites and the presence of some satellite bands were observed by HAADF-STEM and XPS, respectively, though only thermal treatments modified partially or completely the LDH structure. NiCo- and ZnAl-LDH have the weakest and the most stable LDH structures, respectively. Finally, on the unmodified NiFe- and NiCo-, and ZnAl-LDH materials, photoactivity showed zero activity toward H2 production, most likely due to their narrow and wide band gap (BG), respectively, but further thermal modifications, plus the incorporation of co-catalysts such as Pt and TiO2, promoted photocatalytic activity. On the LDH containing TiO2, the modifications had variable effect, for instance, Pt photodeposition significantly enhanced activity on ZnAl-LDH, but not on NiFe-LDH.
{"title":"Layered double hydroxides for H2 generation by the photoreforming of organic compounds","authors":"Sandra Yurani Toledo Camacho , Francisco Mediana Cabello , Sandra Contreras Iglesias , Philip R. Davies , David J. Morgan , Auttaphon Chachvalvutikul","doi":"10.1016/j.cattod.2024.115168","DOIUrl":"10.1016/j.cattod.2024.115168","url":null,"abstract":"<div><div>Layered Double-Hydroxides (LDH) materials are promising catalysts for solar-driven reactions thanks to their two-dimensional and the tunability of their composition. The preparation of three bimetallic NiFe-, NiCo- and ZnAl-LDH for H<sub>2</sub> production by the photoreforming of glycerol under UV and visible irradiation has been investigated. Different modifications were studied: calcination, thermal reduction, plus Pt loading and TiO<sub>2</sub> doping. Samples exhibited typical features of LDHs in XRD and hexagonal crystallites and the presence of some satellite bands were observed by HAADF-STEM and XPS, respectively, though only thermal treatments modified partially or completely the LDH structure. NiCo- and ZnAl-LDH have the weakest and the most stable LDH structures, respectively. Finally, on the unmodified NiFe- and NiCo-, and ZnAl-LDH materials, photoactivity showed zero activity toward H<sub>2</sub> production, most likely due to their narrow and wide band gap (BG), respectively, but further thermal modifications, plus the incorporation of co-catalysts such as Pt and TiO<sub>2</sub>, promoted photocatalytic activity. On the LDH containing TiO<sub>2,</sub> the modifications had variable effect, for instance, Pt photodeposition significantly enhanced activity on ZnAl-LDH, but not on NiFe-LDH.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115168"},"PeriodicalIF":5.2,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-19DOI: 10.1016/j.cattod.2024.115166
Rosembergue Gabriel Lima Gonçalves , Gabriel Liscia Catuzo , José Mansur Assaf , Elisabete Moreira Assaf
This study investigated catalysts derived from layered double hydroxides (LDH) with and without potassium in the Reverse Water Gas-Shift (RWGS) reaction. According to the results, despite the addition of potassium reducing the catalysts´ porosity and altering their morphology, K improved their efficiency by decreasing CH4 production and increasing selectivity towards CO. An evaluation of the K impregnation method demonstrated when not calcined prior to the impregnation process with 5 wt% of K (MgFe/K), the material showed better catalytic performance in comparison to catalysts calcined at 500 (MgFe500/K) and 800 °C (MgFe500/K). Adjustments in parameters such as temperature, gas flow rates, and H2:CO2 ratio offer a pathway for increasing selectivity for CO in the RWGS reaction. In situ DRIFTS analyses revealed changes in bands associated with CO32 − and *HCOO species, offering insights into CO2 activation and suggesting the involvement of formate-mediated pathways as responsible for CO production.
{"title":"Evaluation of the potassium incorporation method in MgFe catalysts derived from layered double hydroxides in the hydrogenation of CO2","authors":"Rosembergue Gabriel Lima Gonçalves , Gabriel Liscia Catuzo , José Mansur Assaf , Elisabete Moreira Assaf","doi":"10.1016/j.cattod.2024.115166","DOIUrl":"10.1016/j.cattod.2024.115166","url":null,"abstract":"<div><div>This study investigated catalysts derived from layered double hydroxides (LDH) with and without potassium in the Reverse Water Gas-Shift (RWGS) reaction. According to the results, despite the addition of potassium reducing the catalysts´ porosity and altering their morphology, K improved their efficiency by decreasing CH<sub>4</sub> production and increasing selectivity towards CO. An evaluation of the K impregnation method demonstrated when not calcined prior to the impregnation process with 5 wt% of K (MgFe/K), the material showed better catalytic performance in comparison to catalysts calcined at 500 (MgFe500/K) and 800 °C (MgFe500/K). Adjustments in parameters such as temperature, gas flow rates, and H<sub>2</sub>:CO<sub>2</sub> ratio offer a pathway for increasing selectivity for CO in the RWGS reaction. <em>In situ</em> DRIFTS analyses revealed changes in bands associated with CO<sub>3</sub><sup>2 −</sup> and *HCOO species, offering insights into CO<sub>2</sub> activation and suggesting the involvement of formate-mediated pathways as responsible for CO production.</div></div>","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115166"},"PeriodicalIF":5.2,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-18DOI: 10.1016/j.cattod.2024.115170
Xinli Tong, Emiel J.M. Hensen, Haichao Liu, De Chen, Matthias Beller, Biaohua Chen, Yongdan Li
{"title":"Preface: Catalysis in biomass to fuel and chemicals (The 4th international symposium on catalytic science and technology in sustainable energy and environment, EECAT2023)","authors":"Xinli Tong, Emiel J.M. Hensen, Haichao Liu, De Chen, Matthias Beller, Biaohua Chen, Yongdan Li","doi":"10.1016/j.cattod.2024.115170","DOIUrl":"10.1016/j.cattod.2024.115170","url":null,"abstract":"","PeriodicalId":264,"journal":{"name":"Catalysis Today","volume":"448 ","pages":"Article 115170"},"PeriodicalIF":5.2,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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