Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of freshwater.Despite much effort made into photothermal materials,there is an urgent need ...Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of freshwater.Despite much effort made into photothermal materials,there is an urgent need to design a rapidly synthesized photothermal evaporator for the comprehensive purification of complex seawater.Therefore,we report on all-in-one FeOx-rGO photothermal sponges synthesized via solid-phase microwave thermal shock.The narrow band gap of the semiconductor material Fe_(3)O_(4) greatly reduces the recombination of electron-hole pairs,enhancing non-radiative relaxation light absorption.The abundantπorbitals in rGO promote electron excitation and thermal vibration between the lattices.Control of the surface hydrophilicity and hydrophobicity promotes salt resistance while simultaneously achieving the purification of various complex polluted waters.The optimized GFM-3 sponge exhibitedan enhanced photothermal conversion rate of 97.3% and a water evaporation rate of 2.04 kg/(m^(2)·hr),showing promising synergistic water purification properties.These findings provide a highly efficient photothermal sponge for practical applicationsof seawater desalination and purification,as well as develop a super-rapid processing methodology for evaporation devices.展开更多
SrxBi1-xFeO3- (SBF) series mixed conductors were synthesized using Standard ceramic method. The properties of such materials were characterized by XRD, O2-TPD techniques. Ab-normal crystal phenomena were found and exp...SrxBi1-xFeO3- (SBF) series mixed conductors were synthesized using Standard ceramic method. The properties of such materials were characterized by XRD, O2-TPD techniques. Ab-normal crystal phenomena were found and explained and correlated with the oxygen permeation results. By analysis of the critical radius (rc), the degree of openness of the lattice (Fv) and the average metal-oxygen bonding energy of the perovskite lattice (ABE), it was proposed that the oxygen permeation flux is determined mainly by the oxygen diffusion rate in bulk when 1-x≤0.5, and by the concentration of oxygen vacancy when 1-x≥ 0.5. The stability of Sr0.5Bi0.5FeO3- was also investigated, and the high stability of it was attributed to the stable BO6 octahedra.展开更多
BiFeO_(3) has been recognized as one of the most important room-temperature single-phase multiferroic materials,but it still suffers from several drawbacks especially the weak magnetoelectric coupling.In the present w...BiFeO_(3) has been recognized as one of the most important room-temperature single-phase multiferroic materials,but it still suffers from several drawbacks especially the weak magnetoelectric coupling.In the present work,the electric-field-controlled magnetism is achieved in Bi_(1-x)Gd_(x)FeO_(3) system,which involves a field-induced transition of Pna2_(1)/R3c at the morphotropic phase boundary region,and the magnetic state is switched between cycloidal state and canted antiferromagnetic state.The electric-field-controlled magnetism becomes reversible with the help of annealing,which is confirmed by magnetic hysteresis loops and the quantitative ratio of the involved phases for the as-sintered,as-poled and as-annealed samples.Compared with the systems of Bi_(1-x)Nd_(x)FeO_(3) and Bi_(1-x)Sm_(x)FeO_(3),it is easier to tune the symmetry from R3c to Pna21 with lower rare earth-content,and the field-induced transition is more apparent and subsequently leads to more significant electric-field-controlled magnetism in a wider composition range.展开更多
The design of efficient iron-based catalysts remains a great challenge for selective cyclohexane oxidation to cyclohexanone under mild conditions.Because of the complex distribution of iron location on the support,the...The design of efficient iron-based catalysts remains a great challenge for selective cyclohexane oxidation to cyclohexanone under mild conditions.Because of the complex distribution of iron location on the support,the selectivity is always low.Here,we report a general strategy to selectively deposit highly-dispersed FeO_(x) into the micropore of ZSM-5 by atomic layer deposition(ALD).The framework of ZSM-5 and the Bronsted acid sites are intact during ALD,and the Fe species are selectively deposited onto the defect and Lewis acid sites of ZSM-5.Besides,more Fe–O–Si bonds are formed over FeO_(x)/ZSM-5 with a low loading of Fe,while FeO_(x) nanoparticles are generated at high Fe loading.They cannot be realized by the traditional solution method.The obtained FeO_(x)/ZSM-5 catalysts perform high selectivity of cyclohexanone(92%–97%),and ALD cycle numbers of FeO_(x) control the activity.Compared with the Fe nanoparticles,the Fe–O–Si species performs higher turnover frequency and stability in the oxidation reaction.展开更多
The study aims to investigate the structural and dielectric properties of perovskite La_(1-x)Sr_(x)FeO_(3)(x=0.1,0.2,0.3,and 0.4)synthesized by solgel and sintering methods.X-ray diffraction(XRD),transmission electron...The study aims to investigate the structural and dielectric properties of perovskite La_(1-x)Sr_(x)FeO_(3)(x=0.1,0.2,0.3,and 0.4)synthesized by solgel and sintering methods.X-ray diffraction(XRD),transmission electron microscopy(TEM),and LCR-Meter were used to identify the phase,crystallography parameters,morphology,particle size,and electrical behavior of the synthesized perovskite materials.The samples showed a single-phase orthorhombic crystal structure with Pbnm space group.Sr-substitution induced the volume unit cell and crystallite size to decrease.The synthesized nanoparticles were uniform and homogeneous with the particle size less than 200 nm.Impedance spectroscopy(IS)was used to explain the electrical behavior as a function of frequency(100 Hz to 1 MHz)at various temperatures(300–373 K).The presence of small polarons as charge carriers within the grain and grain boundary were elucidated from the electrical conductivity experiments.Sr-substitution caused the dielectric constant and electronic conductivity to increase with the highest values obtained from La_(1-x)Sr_(x)FeO_(3)(x=0.4).展开更多
基金supported by the National Natural Science Foundation of China(No.22106105)the Innovation Program of Shanghai Municipal Education Commission(No.2019–01–07–00-E00015)+4 种基金the Shanghai Scientific and Technological Innovation Project(Nos.21DZ1206300 and 19JC1410402)the Scientific and Technological Innovation Team for Green Catalysis and Energy Material in Yunnan Institutions of Higher Learning,General Project of Yunnan Province Science and Technology Department(No.202101BA070001–050)the Central Guidance on Local Science and Technology Development Fund of Shanghai(No.YDZX20213100003002)the Science and Technology Commission of Shanghai Municipality(No.20060502200)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,and Shanghai Sailing Program(No.20YF1432200)。
文摘Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of freshwater.Despite much effort made into photothermal materials,there is an urgent need to design a rapidly synthesized photothermal evaporator for the comprehensive purification of complex seawater.Therefore,we report on all-in-one FeOx-rGO photothermal sponges synthesized via solid-phase microwave thermal shock.The narrow band gap of the semiconductor material Fe_(3)O_(4) greatly reduces the recombination of electron-hole pairs,enhancing non-radiative relaxation light absorption.The abundantπorbitals in rGO promote electron excitation and thermal vibration between the lattices.Control of the surface hydrophilicity and hydrophobicity promotes salt resistance while simultaneously achieving the purification of various complex polluted waters.The optimized GFM-3 sponge exhibitedan enhanced photothermal conversion rate of 97.3% and a water evaporation rate of 2.04 kg/(m^(2)·hr),showing promising synergistic water purification properties.These findings provide a highly efficient photothermal sponge for practical applicationsof seawater desalination and purification,as well as develop a super-rapid processing methodology for evaporation devices.
文摘SrxBi1-xFeO3- (SBF) series mixed conductors were synthesized using Standard ceramic method. The properties of such materials were characterized by XRD, O2-TPD techniques. Ab-normal crystal phenomena were found and explained and correlated with the oxygen permeation results. By analysis of the critical radius (rc), the degree of openness of the lattice (Fv) and the average metal-oxygen bonding energy of the perovskite lattice (ABE), it was proposed that the oxygen permeation flux is determined mainly by the oxygen diffusion rate in bulk when 1-x≤0.5, and by the concentration of oxygen vacancy when 1-x≥ 0.5. The stability of Sr0.5Bi0.5FeO3- was also investigated, and the high stability of it was attributed to the stable BO6 octahedra.
基金The present work was supported by National Key R&D Program of China under grant No.2016YFA0300101(X.M.C.)National Natural Science Foundation of China under grant Nos.51790493 and 51961145105(X.M.C.).
文摘BiFeO_(3) has been recognized as one of the most important room-temperature single-phase multiferroic materials,but it still suffers from several drawbacks especially the weak magnetoelectric coupling.In the present work,the electric-field-controlled magnetism is achieved in Bi_(1-x)Gd_(x)FeO_(3) system,which involves a field-induced transition of Pna2_(1)/R3c at the morphotropic phase boundary region,and the magnetic state is switched between cycloidal state and canted antiferromagnetic state.The electric-field-controlled magnetism becomes reversible with the help of annealing,which is confirmed by magnetic hysteresis loops and the quantitative ratio of the involved phases for the as-sintered,as-poled and as-annealed samples.Compared with the systems of Bi_(1-x)Nd_(x)FeO_(3) and Bi_(1-x)Sm_(x)FeO_(3),it is easier to tune the symmetry from R3c to Pna21 with lower rare earth-content,and the field-induced transition is more apparent and subsequently leads to more significant electric-field-controlled magnetism in a wider composition range.
基金supported by the National Natural Science Foundation of China(21872160,U1832208)the National Science Fund for Distinguished Young Scholars(21825204)+2 种基金the National Key R&D Program of China(2017YFA0700101 and 2018YFB1501602)the Youth Innovation Promotion Association CAS(2017204)Natural Science Foundation of Shanxi Province(201901D211591)。
文摘The design of efficient iron-based catalysts remains a great challenge for selective cyclohexane oxidation to cyclohexanone under mild conditions.Because of the complex distribution of iron location on the support,the selectivity is always low.Here,we report a general strategy to selectively deposit highly-dispersed FeO_(x) into the micropore of ZSM-5 by atomic layer deposition(ALD).The framework of ZSM-5 and the Bronsted acid sites are intact during ALD,and the Fe species are selectively deposited onto the defect and Lewis acid sites of ZSM-5.Besides,more Fe–O–Si bonds are formed over FeO_(x)/ZSM-5 with a low loading of Fe,while FeO_(x) nanoparticles are generated at high Fe loading.They cannot be realized by the traditional solution method.The obtained FeO_(x)/ZSM-5 catalysts perform high selectivity of cyclohexanone(92%–97%),and ALD cycle numbers of FeO_(x) control the activity.Compared with the Fe nanoparticles,the Fe–O–Si species performs higher turnover frequency and stability in the oxidation reaction.
基金Ministry of TechnologyResearch and Higher Education of Republic of Indonesiaunder KLN Grant No. 537/UN2.R3.1/HKP05.00/2018.
文摘The study aims to investigate the structural and dielectric properties of perovskite La_(1-x)Sr_(x)FeO_(3)(x=0.1,0.2,0.3,and 0.4)synthesized by solgel and sintering methods.X-ray diffraction(XRD),transmission electron microscopy(TEM),and LCR-Meter were used to identify the phase,crystallography parameters,morphology,particle size,and electrical behavior of the synthesized perovskite materials.The samples showed a single-phase orthorhombic crystal structure with Pbnm space group.Sr-substitution induced the volume unit cell and crystallite size to decrease.The synthesized nanoparticles were uniform and homogeneous with the particle size less than 200 nm.Impedance spectroscopy(IS)was used to explain the electrical behavior as a function of frequency(100 Hz to 1 MHz)at various temperatures(300–373 K).The presence of small polarons as charge carriers within the grain and grain boundary were elucidated from the electrical conductivity experiments.Sr-substitution caused the dielectric constant and electronic conductivity to increase with the highest values obtained from La_(1-x)Sr_(x)FeO_(3)(x=0.4).
