Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scann...Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scanning electron microscope),and XPS(X-ray photoelectron spectroscopy)and the purification effect on NO_(x) and PM was measured through simulated emission experiments.The results indicate that CuCrO_(2) catalyst has good catalytic activity,the maximum NO_(x) conversion rate can be up to 28.15%,and the ignition temperature of PM can be reduced to 285℃.When the molecular ratio of Cr:Fe=9:1,the catalyst can achieve better catalytic effect,the maximum NO_(x) conversion rate will be up to 30.25%and the PM ignition temperature can be reduced to 280℃.In addition,the catalytic activity of catalyst supported on different carriers was also studied.The results show that catalyst on SiC foam ceramic carrier has better catalytic activity than that on cordierite honeycomb ceramic carrier.The maximum NO_(x) conversion of CuCrO_(2) and CuCr_(0.9)Fe_(0.1)O_(2) can be increased by 0.72%and 1.33%respectively,and the PM ignition temperature can be further reduced by 15 and 5℃respectively.展开更多
This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production fr...This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.展开更多
Fe-doped In2O3 dilute magnetic semiconducting nanowires are fabricated on A u-deposited Si substrates by the chemical vapor deposition technique. It is confirmed by energy dispersive x-ray spectroscopy （EDS）, x-ray ...Fe-doped In2O3 dilute magnetic semiconducting nanowires are fabricated on A u-deposited Si substrates by the chemical vapor deposition technique. It is confirmed by energy dispersive x-ray spectroscopy （EDS）, x-ray photoelectron spectroscopy （XPS） and Raman spectroscopy that Fe has been successfully doped into lattices of In2O3 nanowires. The EDS measurements reveal a large amount of oxygen vacancies existing in the Fe-doped In2O3 nanowires. The Fe dopant exists as a mixture of Fe2＋ and Fe3＋, as revealed by the XPS. The origin of room-temperature ferromagnetism in Fe-doped In2O3 nanowires is explained by the bound magnetic polaron model.展开更多
It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobe...It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobelts were synthesized for purifying metronidazole(MNZ)via PDS activation.As an efficient Fentonlike catalyst for PDS activation,2 wt%Fe-doped VO_(2)can remove 98%of MNZ within 40 min and exhibits impressive recyclability.The synergistic effect of Fe-VO_(2)and Fe(Ⅲ)activated PDS boosted the photocatalytic performance.Moreover,SO_(4)•^(−),h+,O_(2)•^(−),^(1)O_(2),and•OH were the main reactive radicals.The effects of initial MNZ concentration,Fe-VO_(2),PDS dosage,and various anions/cations on MNZ removal by the Fe-VO_(2)/PDS/Vis system were studied.The intermediates of MNZ degradation and possible pathways were determined by density function theory(DFT)calculations and HPLC-MS.This study provided a sustainable technology using Fe-doped ultrathin VO_(2)nanobelts for photocatalytic PDS activation and decontamination of pharmaceutical wastewater.展开更多
基金Funded by National Natural Science Foundation of China(No.52494933)。
文摘Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scanning electron microscope),and XPS(X-ray photoelectron spectroscopy)and the purification effect on NO_(x) and PM was measured through simulated emission experiments.The results indicate that CuCrO_(2) catalyst has good catalytic activity,the maximum NO_(x) conversion rate can be up to 28.15%,and the ignition temperature of PM can be reduced to 285℃.When the molecular ratio of Cr:Fe=9:1,the catalyst can achieve better catalytic effect,the maximum NO_(x) conversion rate will be up to 30.25%and the PM ignition temperature can be reduced to 280℃.In addition,the catalytic activity of catalyst supported on different carriers was also studied.The results show that catalyst on SiC foam ceramic carrier has better catalytic activity than that on cordierite honeycomb ceramic carrier.The maximum NO_(x) conversion of CuCrO_(2) and CuCr_(0.9)Fe_(0.1)O_(2) can be increased by 0.72%and 1.33%respectively,and the PM ignition temperature can be further reduced by 15 and 5℃respectively.
基金funding from the"Ministero dell'Universitàe della Ricerca(MUR)"(Italy)under the"Dipartimento di Eccellenza 2018-2022"program.
文摘This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.
基金Supported by the National Basic Research Program of China under Grant Nos 2014CB921101,2014CB921103 and2013CB922103the National Natural Science Foundation of China under Grant Nos 11274003,61176088 and 61274102+1 种基金the Program for the New Century Excellent Talents in University under Grant No NCET-11-0240the PAPD Project,and the Fundamental Research Funds for the Central Universities
文摘Fe-doped In2O3 dilute magnetic semiconducting nanowires are fabricated on A u-deposited Si substrates by the chemical vapor deposition technique. It is confirmed by energy dispersive x-ray spectroscopy （EDS）, x-ray photoelectron spectroscopy （XPS） and Raman spectroscopy that Fe has been successfully doped into lattices of In2O3 nanowires. The EDS measurements reveal a large amount of oxygen vacancies existing in the Fe-doped In2O3 nanowires. The Fe dopant exists as a mixture of Fe2＋ and Fe3＋, as revealed by the XPS. The origin of room-temperature ferromagnetism in Fe-doped In2O3 nanowires is explained by the bound magnetic polaron model.
基金the financial supports from the National Key Research and Development Program of China(Nos.2021YFB3500600,2021YFB3500605,2022YFB3504100)Key R&D Program of Jiangsu Province(No.BE2022142)+6 种基金Ministry of Education Chunhui plan international cooperation project(No.202200554)National Natural Science Foundation of China(No.grant 22208170)Natural Science Foundation of Inner Mongolia(No.2021BS02016)Jiangsu International Cooperation Project(No.BZ2021018)Nanjing Science and Technology Top Experts Gathering Plan,and Open Foundation of State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control(No.SEMPC2023004)Cooperation Foundation for the Chunhui Plan Program of Ministry of Education of China(No.202200554)Open Project Program of Key Laboratory of Opticelectric Sensing and Analytical Chemistry for Life Science(No.M2024-7),MOE。
文摘It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobelts were synthesized for purifying metronidazole(MNZ)via PDS activation.As an efficient Fentonlike catalyst for PDS activation,2 wt%Fe-doped VO_(2)can remove 98%of MNZ within 40 min and exhibits impressive recyclability.The synergistic effect of Fe-VO_(2)and Fe(Ⅲ)activated PDS boosted the photocatalytic performance.Moreover,SO_(4)•^(−),h+,O_(2)•^(−),^(1)O_(2),and•OH were the main reactive radicals.The effects of initial MNZ concentration,Fe-VO_(2),PDS dosage,and various anions/cations on MNZ removal by the Fe-VO_(2)/PDS/Vis system were studied.The intermediates of MNZ degradation and possible pathways were determined by density function theory(DFT)calculations and HPLC-MS.This study provided a sustainable technology using Fe-doped ultrathin VO_(2)nanobelts for photocatalytic PDS activation and decontamination of pharmaceutical wastewater.
