Zhi-You Su, Baolan Yu, Jianxin Feng, Maoling Zhong, Xuan Li, Jianying Shi
The molecular complexes of Re(4,4′-dcbpy)(CO)3Cl (dcbpy = dicarboxylicacid-2,2’-bipyridyl) and [Ru(dcbpy)3]2+ are co-assembled into UiO-66 scaffolds as structural imperfects for CO2 photocatalytic reduction (named as Re-Ru@U). The prepared catalysts are characterized by XRD, Fourier-Transform infrared (FTIR) spectra, X-ray photoelectron spectra (XPS) and N2 adsorption–desorption isotherms. The intact structure of molecular complexes within the matrix are monitored by 1H nuclear magnetic resonance (NMR) spectra through a totally digesting catalyst. The optical properties are studied via absorption and photoluminescence spectra, and the single-electron reduction in Re and Ru complexes is detected by electron paramagnetic resonance (EPR) spectra. An excellent photocatalytic performance is obtained with steady and sustained CO evolution and a turnover number (TON) value of 15 (11 h). The CO activity irradiating by single wavelength presents the absorption-intensity-dependent changing tendency, where the absorption intensity is superposed by Re and Ru complexes. The two radicals related to Re and Ru, respectively, are simultaneously detected in the Re-Ru@U catalyst. It is suggested that the ReC2 component serves as both a photosensitizer and a catalyst, and the RuC2 component works as an additional photosensitizer to supply the second electron for CO2 reduction. The co-assembling of dual metals Re and Ru in the matrix promotes the electron transfer from the reductive Ru centres to one-electron-reduced Re centres and accounts for the superior activity of CO evolution. Our results demonstrate a strategy to develop the multimetallic catalysts via facile assembling into MOF scaffolds to promote photocatalytic performance.
Re(4,4′-dcbpy)(CO)3Cl（dcbpy = 二羧酸-2,2'-联吡啶基）和[Ru(dcbpy)3]2+分子复合物共同组装到 UiO-66 支架中，作为二氧化碳光催化还原的结构不完善体（命名为 Re-Ru@U）。利用 XRD、傅立叶变换红外光谱（FTIR）、X 射线光电子能谱（XPS）和 N2 吸附-解吸等温线对制备的催化剂进行了表征。通过完全消解催化剂，利用 1H 核磁共振（NMR）光谱监测基质内分子复合物的完整结构。通过吸收光谱和光致发光光谱研究了其光学特性，并通过电子顺磁共振（EPR）光谱检测了 Re 和 Ru 复合物中的单电子还原。该化合物具有优异的光催化性能，能稳定、持续地转化 CO，其周转次数（TON）值为 15（11 小时）。单一波长照射下的 CO 活性呈现出吸收强度依赖性变化趋势，其中 Re 和 Ru 复合物的吸收强度叠加。在 Re-Ru@U 催化剂中同时检测到了分别与 Re 和 Ru 有关的两种自由基。这表明 ReC2 成分既是光敏剂又是催化剂，而 RuC2 成分则作为额外的光敏剂为二氧化碳还原提供第二个电子。双金属 Re 和 Ru 在基质中的共组装促进了还原型 Ru 中心向单电子还原型 Re 中心的电子转移，这也是 CO 演化活性更强的原因。我们的研究结果展示了一种开发多金属催化剂的策略，即通过简单地组装到 MOF 支架中来提高光催化性能。
{"title":"Co-Encapsulation of Rhenium and Ruthenium Complexes into the Scaffolds of Metal–Organic Framework to Promote CO2 Reduction","authors":"Zhi-You Su, Baolan Yu, Jianxin Feng, Maoling Zhong, Xuan Li, Jianying Shi","doi":"10.3390/catal13121510","DOIUrl":"https://doi.org/10.3390/catal13121510","url":null,"abstract":"The molecular complexes of Re(4,4′-dcbpy)(CO)3Cl (dcbpy = dicarboxylicacid-2,2’-bipyridyl) and [Ru(dcbpy)3]2+ are co-assembled into UiO-66 scaffolds as structural imperfects for CO2 photocatalytic reduction (named as Re-Ru@U). The prepared catalysts are characterized by XRD, Fourier-Transform infrared (FTIR) spectra, X-ray photoelectron spectra (XPS) and N2 adsorption–desorption isotherms. The intact structure of molecular complexes within the matrix are monitored by 1H nuclear magnetic resonance (NMR) spectra through a totally digesting catalyst. The optical properties are studied via absorption and photoluminescence spectra, and the single-electron reduction in Re and Ru complexes is detected by electron paramagnetic resonance (EPR) spectra. An excellent photocatalytic performance is obtained with steady and sustained CO evolution and a turnover number (TON) value of 15 (11 h). The CO activity irradiating by single wavelength presents the absorption-intensity-dependent changing tendency, where the absorption intensity is superposed by Re and Ru complexes. The two radicals related to Re and Ru, respectively, are simultaneously detected in the Re-Ru@U catalyst. It is suggested that the ReC2 component serves as both a photosensitizer and a catalyst, and the RuC2 component works as an additional photosensitizer to supply the second electron for CO2 reduction. The co-assembling of dual metals Re and Ru in the matrix promotes the electron transfer from the reductive Ru centres to one-electron-reduced Re centres and accounts for the superior activity of CO evolution. Our results demonstrate a strategy to develop the multimetallic catalysts via facile assembling into MOF scaffolds to promote photocatalytic performance.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"28 6","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139002905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anatoly Bortun, Mila Bortun, Benjamin Brown, Jeremy Madynski
Series of ceria-zirconia (CZ)-based nano-materials with a d50 in the range of 0.2 to 1.3 microns were made using the jar milling, Eiger milling, and steam jet milling (SJM) techniques. The effect of the milling conditions on the morphology and textural properties was studied. High-energy steam jet milling in a quasi-hydrothermal environment (with potential local temperature spikes over 500 °C) significantly impacted the CZ crystal structure by inducing lattice distortions. It was shown that the acquired lattice stress resulted in a significant increase in oxygen mobility, which was manifested by a TPR-H2 Tmax shift from 450–550 to 150–250 °C. CZ materials with fast oxygen mobility are metastable phases, and re-slurring nano-CZ powders in water and impregnation with precious metals had stabilizing effects on fast oxygen mobility. Efficiently enhancing the CZ redox activity milling process took place in the following order: Steam jet milling > Eiger milling > jar milling.
{"title":"Effect of High-Energy Milling on Ceria-Zirconia’s Redox Properties","authors":"Anatoly Bortun, Mila Bortun, Benjamin Brown, Jeremy Madynski","doi":"10.3390/catal13121511","DOIUrl":"https://doi.org/10.3390/catal13121511","url":null,"abstract":"Series of ceria-zirconia (CZ)-based nano-materials with a d50 in the range of 0.2 to 1.3 microns were made using the jar milling, Eiger milling, and steam jet milling (SJM) techniques. The effect of the milling conditions on the morphology and textural properties was studied. High-energy steam jet milling in a quasi-hydrothermal environment (with potential local temperature spikes over 500 °C) significantly impacted the CZ crystal structure by inducing lattice distortions. It was shown that the acquired lattice stress resulted in a significant increase in oxygen mobility, which was manifested by a TPR-H2 Tmax shift from 450–550 to 150–250 °C. CZ materials with fast oxygen mobility are metastable phases, and re-slurring nano-CZ powders in water and impregnation with precious metals had stabilizing effects on fast oxygen mobility. Efficiently enhancing the CZ redox activity milling process took place in the following order: Steam jet milling > Eiger milling > jar milling.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"18 9","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139002522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. S. Algarni, A. M. Al-Mohaimeed, Naaser A. Y. Abduh, Reem Abdulrahman Habab, Saad Mohammed Alqahtani
In this work, ZnO, SnO2, and their mixed ZnO-SnO2(25%) nanoparticles (NPs) were successfully green synthesized in a straightforward manner with a low-cost and environmentally friendly approach using a banana peel extract. The synthesized nanophotocatalysts were characterized using various techniques including FTIR, XRD, UV-Vis, TEM, SEM, BET, PL, EDS, and TGA. The characterization results showed that the ZnO and SnO2 powders were crystallized in a hexagonal wurtzite and rutile-type tetragonal structures, respectively, and their mixed ZnO-SnO2(25%) NPs contain both structures. Also, it was found that the addition of SnO2 into the ZnO structure reduces the PL intensity of the latter, confirming better separation of electron/hole pairs. The average particle size of a ZnO-SnO2(25%) NP photocatalyst was found to be 7.23 nm. The cationic dyes methylene blue (MB) and crystal violet (CV) as well as the anionic dyes naphthol blue black (NBB) and Coomassie brilliant blue R 250 (CBB) were employed as model dyes to assess the dye removal efficiencies of the biosynthesized nanophotocatalysts under sunlight. In all cases, the mixed ZnO-SnO2(25%) NP photocatalyst showed much better photocatalytic activity than individual photocatalysts. The degradation percent of dyes using ZnO-SnO2(25%) NPs ranged between 92.2% and 98%. The efficient photocatalytic activity of ZnO-SnO2(25%) NPs is attributed to the effective charge separation and reduced electron/hole recombination rate. The kinetic study results conformed to a pseudo first-order reaction rationalized in terms of the Langmuir–Hinshelwood model. Furthermore, the results showed that the ZnO-SnO2(25%) NP photocatalyst is highly stable and could be recycled several times without a noticeable reduction in its catalytic activity towards dye removal.
{"title":"Green Synthesis of Mixed ZnO-SnO2 Nanoparticles for Solar-Assisted Degradation of Synthetic Dyes","authors":"T. S. Algarni, A. M. Al-Mohaimeed, Naaser A. Y. Abduh, Reem Abdulrahman Habab, Saad Mohammed Alqahtani","doi":"10.3390/catal13121509","DOIUrl":"https://doi.org/10.3390/catal13121509","url":null,"abstract":"In this work, ZnO, SnO2, and their mixed ZnO-SnO2(25%) nanoparticles (NPs) were successfully green synthesized in a straightforward manner with a low-cost and environmentally friendly approach using a banana peel extract. The synthesized nanophotocatalysts were characterized using various techniques including FTIR, XRD, UV-Vis, TEM, SEM, BET, PL, EDS, and TGA. The characterization results showed that the ZnO and SnO2 powders were crystallized in a hexagonal wurtzite and rutile-type tetragonal structures, respectively, and their mixed ZnO-SnO2(25%) NPs contain both structures. Also, it was found that the addition of SnO2 into the ZnO structure reduces the PL intensity of the latter, confirming better separation of electron/hole pairs. The average particle size of a ZnO-SnO2(25%) NP photocatalyst was found to be 7.23 nm. The cationic dyes methylene blue (MB) and crystal violet (CV) as well as the anionic dyes naphthol blue black (NBB) and Coomassie brilliant blue R 250 (CBB) were employed as model dyes to assess the dye removal efficiencies of the biosynthesized nanophotocatalysts under sunlight. In all cases, the mixed ZnO-SnO2(25%) NP photocatalyst showed much better photocatalytic activity than individual photocatalysts. The degradation percent of dyes using ZnO-SnO2(25%) NPs ranged between 92.2% and 98%. The efficient photocatalytic activity of ZnO-SnO2(25%) NPs is attributed to the effective charge separation and reduced electron/hole recombination rate. The kinetic study results conformed to a pseudo first-order reaction rationalized in terms of the Langmuir–Hinshelwood model. Furthermore, the results showed that the ZnO-SnO2(25%) NP photocatalyst is highly stable and could be recycled several times without a noticeable reduction in its catalytic activity towards dye removal.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"3 8‐9","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139004991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhijiang Ni, Mingxing Cai, Shiyu Zhong, Xiaoyu Chen, Hanyu Shen, Lin Su
A prepared FeZnNa@SiO2-C catalyst with graphitized carbon (C)-modified mesoporous SiO2 supports metal nanoparticles with the sol–gel method. The effect of adding metal Na and Zn promoters as a dispersion on the CO2 hydrogenation to low olefins was systematically studied. The results showed that Zn–Na, as a combination, could promote the absorption of CO2 and improved the conversion rate of CO2. Na as an alkaline substance can improve the absorption of more acidic CO2, which could increase the conversion rate of CO2 to 59.03%. Meanwhile, the addition of secondary metal Zn to Fe-based catalysts to form a surface alloy could alter the adsorption of CO2 and the activation of C-O bonds, inhibit the subsequent hydrogenation of olefins to paraffins, and facilitate the reduction of Fe2O3 and the formation of active Fe5C2 species. The formation of active Fe5C2 species was found in TEM and XRD, and the selectivity of the target product was 41.07%. The deep hydrogenation of olefins was inhibited, and the space–time yield (STY) of low olefins was raised again by inhibiting their deep hydrogenations, up to 0.0436. However, the corresponding STY did not increase infinitely with the increase of Na doping, and higher catalytic performance for CO2 hydrogenation could be exhibited when the Na doping reached 6.4%. Compared with Fe@SiO2-C catalyst, Na- and Zn-promoted Fe-based catalysts, prepared by the modified sol-gel method, can be used directly for highly efficient CO2 hydrogenation to low olefins and thus has a more promising application prospect in the future.
采用溶胶-凝胶法制备了FeZnNa@SiO2-C催化剂，该催化剂以石墨化碳（C）修饰的介孔SiO2为金属纳米颗粒支撑。系统研究了添加分散金属 Na 和 Zn 促进剂对 CO2 加氢制取低烯烃的影响。结果表明，Zn-Na 组合能促进 CO2 的吸收，提高 CO2 的转化率。Na 作为一种碱性物质，可以改善对酸性较强的 CO2 的吸收，从而将 CO2 的转化率提高到 59.03%。同时，在铁基催化剂中加入次生金属 Zn 形成表面合金，可以改变 CO2 的吸附和 C-O 键的活化，抑制烯烃向石蜡的后续氢化，促进 Fe2O3 的还原和活性 Fe5C2 物种的形成。在 TEM 和 XRD 中发现了活性 Fe5C2 物种的形成，目标产物的选择性为 41.07%。通过抑制烯烃的深度氢化，低烯烃的时空产率（STY）再次提高，达到 0.0436。然而，相应的 STY 并没有随着 Na 掺杂量的增加而无限提高，当 Na 掺杂量达到 6.4% 时，CO2 加氢的催化性能更高。与Fe@SiO2-C催化剂相比，改良溶胶-凝胶法制备的Na-和Zn促进的Fe基催化剂可直接用于高效CO2加氢制取低烯烃，因此在未来具有更广阔的应用前景。
{"title":"Sodium Promoted FeZn@SiO2-C Catalysts for Sustainable Production of Low Olefins by CO2 Hydrogenation","authors":"Zhijiang Ni, Mingxing Cai, Shiyu Zhong, Xiaoyu Chen, Hanyu Shen, Lin Su","doi":"10.3390/catal13121508","DOIUrl":"https://doi.org/10.3390/catal13121508","url":null,"abstract":"A prepared FeZnNa@SiO2-C catalyst with graphitized carbon (C)-modified mesoporous SiO2 supports metal nanoparticles with the sol–gel method. The effect of adding metal Na and Zn promoters as a dispersion on the CO2 hydrogenation to low olefins was systematically studied. The results showed that Zn–Na, as a combination, could promote the absorption of CO2 and improved the conversion rate of CO2. Na as an alkaline substance can improve the absorption of more acidic CO2, which could increase the conversion rate of CO2 to 59.03%. Meanwhile, the addition of secondary metal Zn to Fe-based catalysts to form a surface alloy could alter the adsorption of CO2 and the activation of C-O bonds, inhibit the subsequent hydrogenation of olefins to paraffins, and facilitate the reduction of Fe2O3 and the formation of active Fe5C2 species. The formation of active Fe5C2 species was found in TEM and XRD, and the selectivity of the target product was 41.07%. The deep hydrogenation of olefins was inhibited, and the space–time yield (STY) of low olefins was raised again by inhibiting their deep hydrogenations, up to 0.0436. However, the corresponding STY did not increase infinitely with the increase of Na doping, and higher catalytic performance for CO2 hydrogenation could be exhibited when the Na doping reached 6.4%. Compared with Fe@SiO2-C catalyst, Na- and Zn-promoted Fe-based catalysts, prepared by the modified sol-gel method, can be used directly for highly efficient CO2 hydrogenation to low olefins and thus has a more promising application prospect in the future.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"56 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139009658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G.J. Zhaksylykova, K. Shalmagambetov, F. Kanapiyeva, N. Kudaibergenov, M. Bulybayev, Meruyert Zykai, G. Abyzbekova, Gulzhan Balykbayeva
In this work, the activity of various alcohols in the hexene-1 hydroalkoxycarbonylation reaction in the presence of two catalytic systems was investigated for the first time: (1) Pd(PPh3)4-PPh3-TsOH (menthol, cyclohexanol, ethanol, propanol, iso-propanol, butanol, isobutanol and benzyl alcohol) and (2) PdCl2(PPh3)2-PPh3-AlCl3 (ethanol, propanol-1, butanol-1, isoamyl alcohol, isobutanol, pentanol-1, allyl alcohol and tert-butyl alcohol). The optimal process parameters (temperature, pressure and reaction time) for the reactions of the hydropropoxycarbonylation and hydrobutoxycarbonylation of hexene-1, at which the yields of target products reached 91.8% and 91.5%, respectively, were determined.
{"title":"The Role of Alcohols in the Hexene-1 Hydroalkoxycarbonylation Reaction with Catalysts Based on Palladium Complexes","authors":"G.J. Zhaksylykova, K. Shalmagambetov, F. Kanapiyeva, N. Kudaibergenov, M. Bulybayev, Meruyert Zykai, G. Abyzbekova, Gulzhan Balykbayeva","doi":"10.3390/catal13121507","DOIUrl":"https://doi.org/10.3390/catal13121507","url":null,"abstract":"In this work, the activity of various alcohols in the hexene-1 hydroalkoxycarbonylation reaction in the presence of two catalytic systems was investigated for the first time: (1) Pd(PPh3)4-PPh3-TsOH (menthol, cyclohexanol, ethanol, propanol, iso-propanol, butanol, isobutanol and benzyl alcohol) and (2) PdCl2(PPh3)2-PPh3-AlCl3 (ethanol, propanol-1, butanol-1, isoamyl alcohol, isobutanol, pentanol-1, allyl alcohol and tert-butyl alcohol). The optimal process parameters (temperature, pressure and reaction time) for the reactions of the hydropropoxycarbonylation and hydrobutoxycarbonylation of hexene-1, at which the yields of target products reached 91.8% and 91.5%, respectively, were determined.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"21 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139010055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenxi Zhang, X. Cao, Lili Guo, Zhihao Fang, Di Feng, Xiaomin Sun
With the advances in engine technology, the exhaust gas temperature of automobiles has further reduced, which in turn leads to an increase in the emissions of carbon monoxide (CO) and hydrocarbons (HCs). In order to understand the influence of CeO2-based catalysts loaded with different noble metals on the catalytic oxidation activity of CO and HCs, this study constructed catalyst models of Ce0.875Zr0.125O2 (100) surfaces loaded with Pt, Pd, Ag, and Au. The electronic density and state density structures of the catalysts were analyzed, and the reaction energy barriers for CO oxidation and C3H6 dehydrogenation oxidation on the catalyst surfaces were also calculated. Furthermore, the activity sequences of the catalysts were explored. The results revealed that after loading Pt, Pd, Ag, and Au atoms onto the catalyst surfaces, these noble metal atoms exhibited strong interactions with the catalyst surfaces, and electron transfer occurred between the noble metal atoms and the catalyst surfaces. Loading with noble metals can enhance the catalytic activity of CO oxidation, but it has little effect on the dehydrogenation oxidation of C3H6. Of the different noble metals, loading with Pd exhibits the best catalytic activity for both CO and C3H6 oxidation. This study elucidated the influence of noble metal doping on the catalytic activity of catalysts at the molecular level, providing theoretical guidance for the design of a new generation of green and efficient catalysts.
{"title":"Carbon Monoxide and Propylene Catalytic Oxidation Activity of Noble Metals (M = Pt, Pd, Ag, and Au) Loaded on the Surface of Ce0.875Zr0.125O2 (110)","authors":"Chenxi Zhang, X. Cao, Lili Guo, Zhihao Fang, Di Feng, Xiaomin Sun","doi":"10.3390/catal13121505","DOIUrl":"https://doi.org/10.3390/catal13121505","url":null,"abstract":"With the advances in engine technology, the exhaust gas temperature of automobiles has further reduced, which in turn leads to an increase in the emissions of carbon monoxide (CO) and hydrocarbons (HCs). In order to understand the influence of CeO2-based catalysts loaded with different noble metals on the catalytic oxidation activity of CO and HCs, this study constructed catalyst models of Ce0.875Zr0.125O2 (100) surfaces loaded with Pt, Pd, Ag, and Au. The electronic density and state density structures of the catalysts were analyzed, and the reaction energy barriers for CO oxidation and C3H6 dehydrogenation oxidation on the catalyst surfaces were also calculated. Furthermore, the activity sequences of the catalysts were explored. The results revealed that after loading Pt, Pd, Ag, and Au atoms onto the catalyst surfaces, these noble metal atoms exhibited strong interactions with the catalyst surfaces, and electron transfer occurred between the noble metal atoms and the catalyst surfaces. Loading with noble metals can enhance the catalytic activity of CO oxidation, but it has little effect on the dehydrogenation oxidation of C3H6. Of the different noble metals, loading with Pd exhibits the best catalytic activity for both CO and C3H6 oxidation. This study elucidated the influence of noble metal doping on the catalytic activity of catalysts at the molecular level, providing theoretical guidance for the design of a new generation of green and efficient catalysts.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"17 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138632979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anish Clastin Indira, Jayarajan Muthaian, M. Pandi, Faruq Mohammad, H. Al-Lohedan, A. A. Soleiman
The recent advancement in the production of nanomaterials with novel architectures and functionality has allowed for the effective treatment of industrial wastewaters and contaminated soil and, in that view, the current study aimed to investigate the catalytic efficacy of biopolymer-loaded titanium nanocomposite. Therefore, Cerium (Ce)-titanium dioxide (TiO2) loaded chitosan nanocomposite was formed and studied its catalytic efficacy towards the degradation of an industrial dye pollutant. For the production of Ce-TiO2/chitosan nanocomposite, we followed the hydrothermal synthesis route and the formed nanocomposite was thoroughly analyzed for the crystallinity (using powdered X-ray diffraction, XRD), surface bonding, and nature (using Fourier transform infrared, FTIR spectroscopy), morphology (scanning electron microscopy, SEM), elemental composition (electron diffraction analysis by X-rays, EDAX), porosity (Brunauer–Emmett–Teller, BET), and particles size in powdered form (transmission electron microscopy, TEM). Then the efficiency of synthesized nanocomposite was tested towards the photocatalytic degradation of Rhodamine B (Rh B) dye by applying various parameters such as the irradiation time, solution pH, catalyst dosage, and the dye concentration. Further, the Langmuir–Hinshelwood model was employed to investigate the kinetics of RhB degradation and provided a conceivable photocatalytic mechanism. It was indicated based on the catalyst mechanism that the modification of TiO2 nanoparticles with Ce and loading onto chitosan biopolymer may have accelerated the photocurrent transport due to an increase in the number of electrons and holes generated by the photon’s irradiation. In this way, the study has witnessed the excellent photocatalytic performance of Ce-TiO2/chitosan with 95% Rh B degradation as against the pure TiO2 nanoparticles thus stressing the importance of developing novel composite photocatalysts.
最近在生产具有新型结构和功能的纳米材料方面取得的进展使得有效处理工业废水和受污染土壤成为可能，因此，本研究旨在调查负载生物聚合物的钛纳米复合材料的催化功效。因此，研究人员制备了负载壳聚糖的铈（Ce）-二氧化钛（TiO2）纳米复合材料，并研究了其对降解工业染料污染物的催化功效。为了制备 Ce-TiO2/ 壳聚糖纳米复合材料，我们采用了水热合成路线，并对所形成的纳米复合材料的结晶度（使用粉末 X 射线衍射，XRD）、表面键合和性质（使用傅立叶变换红外光谱，FTIR）进行了全面分析、傅立叶变换红外光谱）、形貌（扫描电子显微镜，SEM）、元素组成（X 射线电子衍射分析，EDAX）、孔隙率（布鲁纳-艾美特-泰勒，BET）和粉末状颗粒大小（透射电子显微镜，TEM）。然后，通过应用各种参数，如照射时间、溶液 pH 值、催化剂用量和染料浓度，测试了合成纳米复合材料光催化降解罗丹明 B（Rh B）染料的效率。此外，还采用 Langmuir-Hinshelwood 模型研究了 RhB 降解动力学，并提供了一种可想象的光催化机理。根据催化机理，研究表明，用 Ce 修饰 TiO2 纳米粒子并将其负载到壳聚糖生物聚合物上，可能会由于光子照射产生的电子和空穴数量增加而加速光电流传输。由此可见，与纯 TiO2 纳米粒子相比，Ce-TiO2/壳聚糖具有卓越的光催化性能，Rh B 降解率高达 95%，从而强调了开发新型复合光催化剂的重要性。
{"title":"Photocatalytic Efficacy and Degradation Kinetics of Chitosan-Loaded Ce-TiO2 Nanocomposite towards for Rhodamine B Dye","authors":"Anish Clastin Indira, Jayarajan Muthaian, M. Pandi, Faruq Mohammad, H. Al-Lohedan, A. A. Soleiman","doi":"10.3390/catal13121506","DOIUrl":"https://doi.org/10.3390/catal13121506","url":null,"abstract":"The recent advancement in the production of nanomaterials with novel architectures and functionality has allowed for the effective treatment of industrial wastewaters and contaminated soil and, in that view, the current study aimed to investigate the catalytic efficacy of biopolymer-loaded titanium nanocomposite. Therefore, Cerium (Ce)-titanium dioxide (TiO2) loaded chitosan nanocomposite was formed and studied its catalytic efficacy towards the degradation of an industrial dye pollutant. For the production of Ce-TiO2/chitosan nanocomposite, we followed the hydrothermal synthesis route and the formed nanocomposite was thoroughly analyzed for the crystallinity (using powdered X-ray diffraction, XRD), surface bonding, and nature (using Fourier transform infrared, FTIR spectroscopy), morphology (scanning electron microscopy, SEM), elemental composition (electron diffraction analysis by X-rays, EDAX), porosity (Brunauer–Emmett–Teller, BET), and particles size in powdered form (transmission electron microscopy, TEM). Then the efficiency of synthesized nanocomposite was tested towards the photocatalytic degradation of Rhodamine B (Rh B) dye by applying various parameters such as the irradiation time, solution pH, catalyst dosage, and the dye concentration. Further, the Langmuir–Hinshelwood model was employed to investigate the kinetics of RhB degradation and provided a conceivable photocatalytic mechanism. It was indicated based on the catalyst mechanism that the modification of TiO2 nanoparticles with Ce and loading onto chitosan biopolymer may have accelerated the photocurrent transport due to an increase in the number of electrons and holes generated by the photon’s irradiation. In this way, the study has witnessed the excellent photocatalytic performance of Ce-TiO2/chitosan with 95% Rh B degradation as against the pure TiO2 nanoparticles thus stressing the importance of developing novel composite photocatalysts.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"35 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138979818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The novel ternary composites BiOBr-TiO2-attapulgite (BTA) were synthesized using a simple hydrothermal and water-bath method, exhibiting excellent photocatalytic performance to multiple xanthates. For the BTA photocatalyst, TiO2 and BiOBr were uniformly loaded onto the surface of acid-activated attapulgite. As a widely used collector in mining processes, sodium ethyl-xanthate (SEX) was selected as the target pollutant due to its high toxicity. The BTA ternary photocatalyst demonstrated significantly higher adsorption and photocatalytic degradation performance compared to TiO2 nanoparticles, BiOBr nanosheets, and BiOBr-TiO2 heterojunction. Structural characterization and experimental results indicated that the exceptional photocatalytic degradation efficiency of BTA was mainly attributed to the formation of a heterojunction between BiOBr and TiO2, as well as the presence of additional active adsorption sites provided by attapulgite. Free radical scavenging experiments and EPR results confirmed that the photogenerated holes were the predominant active species in photodegrading SEX throughout the entire experiment. The LC-MS results provided insight into potential degradation pathways of SEX. This research demonstrates that BTA, as a novel triple composite material, achieves rapid and complete degradation to 20 mg/L SEX within 20 min. This work presents a novel approach to synthesize mineral-based photocatalysts, which have broad prospects for application in flotation wastewater treatment.
{"title":"Visible-Light-Driven BiOBr-TiO2-Attapulgite Photocatalyst with Excellent Photocatalytic Activity for Multiple Xanthates","authors":"Yao-zhong Qi, Sikai Zhao, Xiaoyu Jiang, Zhangke Kang, Shuling Gao, Wengang Liu, Yan-bai Shen","doi":"10.3390/catal13121504","DOIUrl":"https://doi.org/10.3390/catal13121504","url":null,"abstract":"The novel ternary composites BiOBr-TiO2-attapulgite (BTA) were synthesized using a simple hydrothermal and water-bath method, exhibiting excellent photocatalytic performance to multiple xanthates. For the BTA photocatalyst, TiO2 and BiOBr were uniformly loaded onto the surface of acid-activated attapulgite. As a widely used collector in mining processes, sodium ethyl-xanthate (SEX) was selected as the target pollutant due to its high toxicity. The BTA ternary photocatalyst demonstrated significantly higher adsorption and photocatalytic degradation performance compared to TiO2 nanoparticles, BiOBr nanosheets, and BiOBr-TiO2 heterojunction. Structural characterization and experimental results indicated that the exceptional photocatalytic degradation efficiency of BTA was mainly attributed to the formation of a heterojunction between BiOBr and TiO2, as well as the presence of additional active adsorption sites provided by attapulgite. Free radical scavenging experiments and EPR results confirmed that the photogenerated holes were the predominant active species in photodegrading SEX throughout the entire experiment. The LC-MS results provided insight into potential degradation pathways of SEX. This research demonstrates that BTA, as a novel triple composite material, achieves rapid and complete degradation to 20 mg/L SEX within 20 min. This work presents a novel approach to synthesize mineral-based photocatalysts, which have broad prospects for application in flotation wastewater treatment.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"540 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138982840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The usability of glass fibers as immobilization support with a porous open structure was investigated. We developed a method to immobilize the enzyme β-galactosidase on special glass fiber rolls. The new method is simple, non-expensive and industrially applicable. Glutaraldehyde was used as a non-specific cross-linking agent for the covalent binding of β-galactosidase on modified glass fibers. The efficiency of immobilization was tested with the known hydrolysis of lactose. All experiments were performed in a continuous laboratory reactor. The influence of the reaction temperature (20, 25 and 30 °C), the substrate flow rate (1, 2 and 3 mL/min) and the pH of the reaction medium (6, 7 and 8) on the conversion was investigated. The reaction efficiency was monitored by measuring the glucose concentration with a spectrophotometer. High immobilization efficiency, enzyme activity and stability were obtained. The optimal reaction temperature, substrate flow rate and pH were found. The activity and stability of the enzyme entrapped on the glass fiber rolls remained almost unchanged during reuse, which is promising for potential industrial applications.
{"title":"The Immobilization of β-Galactosidase on Glass Fiber Rolls","authors":"D. Pečar, Katja Zečević, A. Goršek","doi":"10.3390/catal13121503","DOIUrl":"https://doi.org/10.3390/catal13121503","url":null,"abstract":"The usability of glass fibers as immobilization support with a porous open structure was investigated. We developed a method to immobilize the enzyme β-galactosidase on special glass fiber rolls. The new method is simple, non-expensive and industrially applicable. Glutaraldehyde was used as a non-specific cross-linking agent for the covalent binding of β-galactosidase on modified glass fibers. The efficiency of immobilization was tested with the known hydrolysis of lactose. All experiments were performed in a continuous laboratory reactor. The influence of the reaction temperature (20, 25 and 30 °C), the substrate flow rate (1, 2 and 3 mL/min) and the pH of the reaction medium (6, 7 and 8) on the conversion was investigated. The reaction efficiency was monitored by measuring the glucose concentration with a spectrophotometer. High immobilization efficiency, enzyme activity and stability were obtained. The optimal reaction temperature, substrate flow rate and pH were found. The activity and stability of the enzyme entrapped on the glass fiber rolls remained almost unchanged during reuse, which is promising for potential industrial applications.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"47 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138983289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yao Tian, Xiubin Bu, Yuanrui Chen, Luohe Wang, Junnan E, Jing Zeng, Hao Xu, Aihong Han, Xiaobo Yang, Zhen Zhao
The glycine motif is widely prevalent in bioactive peptides. Thus, the direct and precise modification of glycine derivatives has attracted significant attention over the past few decades. Among various protocols for the modification of glycine derivatives, the visible-light-driven direct α-C(sp3)–H bond functionalization of glycine derivatives has emerged as a powerful tool to achieve this objective, owing to its merits in atom economy, selectivity, reaction simplicity, and sustainability. This review summarizes the recent advancements in visible-light-driven direct α-C(sp3)–H bond functionalization of glycine derivatives. The contents of this review are organized based on the photocatalysts employed and the various reaction modes in the functionalization process. The mechanism, the challenges encountered, and future trends are also discussed, enabling readers to understand the current developmental status in this field.
{"title":"Visible-Light-Driven α-C(sp3)–H Bond Functionalization of Glycine Derivatives","authors":"Yao Tian, Xiubin Bu, Yuanrui Chen, Luohe Wang, Junnan E, Jing Zeng, Hao Xu, Aihong Han, Xiaobo Yang, Zhen Zhao","doi":"10.3390/catal13121502","DOIUrl":"https://doi.org/10.3390/catal13121502","url":null,"abstract":"The glycine motif is widely prevalent in bioactive peptides. Thus, the direct and precise modification of glycine derivatives has attracted significant attention over the past few decades. Among various protocols for the modification of glycine derivatives, the visible-light-driven direct α-C(sp3)–H bond functionalization of glycine derivatives has emerged as a powerful tool to achieve this objective, owing to its merits in atom economy, selectivity, reaction simplicity, and sustainability. This review summarizes the recent advancements in visible-light-driven direct α-C(sp3)–H bond functionalization of glycine derivatives. The contents of this review are organized based on the photocatalysts employed and the various reaction modes in the functionalization process. The mechanism, the challenges encountered, and future trends are also discussed, enabling readers to understand the current developmental status in this field.","PeriodicalId":9794,"journal":{"name":"Catalysts","volume":"194 ","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139011400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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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