With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environmen...With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environments, thereby endangering human health. Therefore, in this paper, a novel functionalized mesoporous adsorbent PPR-Z was synthesized from waste amidoxime resin for adsorbing Cr(Ⅵ). The waste amidoxime resin was first modified with H3PO4 and ZnCl_(2), and subsequently, it was carbonized through slow thermal decomposition. The static adsorption of PPR-Z conforms to the pseudo-second-order kinetic model and Langmuir isotherm, indicating that the Cr(Ⅵ) adsorption by PPR-Z is mostly chemical adsorption and exhibits single-layer adsorption. The saturated adsorption capacity of the adsorbent for Cr(Ⅵ) could reach 255.86 mg/g. The adsorbent could effectively reduce Cr(Ⅵ) to Cr(Ⅲ) and decrease the toxicity of Cr(Ⅵ) during adsorption. PPR-Z exhibited Cr(Ⅵ) selectivity in electroplating wastewater. The main mechanisms involved in the Cr(Ⅵ) adsorption are the chemical reduction of Cr(Ⅵ) into Cr(Ⅲ) and electrostatic and coordination interactions. Preparation of PPR-Z not only solves the problem of waste resin treatment but also effectively controls Cr(Ⅵ) pollution and realizes the concept of “treating waste with waste”.展开更多
A new zinc hydrogen phosphite C4H8N2H4·Zn（HPO3）2 was prepared by hydrothermal method in the presence of piperazine as a structure-directing agent and the crystal structure was determined by single-crystal X-ray...A new zinc hydrogen phosphite C4H8N2H4·Zn（HPO3）2 was prepared by hydrothermal method in the presence of piperazine as a structure-directing agent and the crystal structure was determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, IR, ICP, elemental analysis and TG analysis. This compound has one-dimensional anionic chains containing four-membered rings built from corner-sharing linked alternating ZnO4 tetrahedra and HPO3 pseudo pyramids. The zinc hydrogen phosphite chains are interacted with the templates of diprotonated piperazine by N—H…O hydrogen bond. Crystal data for C4H8N2H4·Zn（HPO3）2∶monoclinic, space group C2/c. a=1.774 8（2） nm, b=0.724 28（9） nm, c=0.880 87（11） nm, β= 105.345（3）°, V=1.091 9（2） nm 3, Z=4, Dc=1^907 Mg/m 3, R1=0.022 9, wR2=0.058 8.展开更多
Direct-Z-scheme g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)photocatalyst with giant internal electric field was prepared by onestep aqueous sonication self-assembly method using g-C_(3)N_(4)and MXene of Ti_(3)C_(2)as the source ...Direct-Z-scheme g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)photocatalyst with giant internal electric field was prepared by onestep aqueous sonication self-assembly method using g-C_(3)N_(4)and MXene of Ti_(3)C_(2)as the source materials.The chemical composition and structure of the catalysts was characterized by FT-IR,XRD,SEM,TEM,and XPS.The XPS characterization indicated that Ti_(3)C_(2)was partially oxidized to TiO_(2)during the composite process.As a result,an efficient direct-Z-scheme heterojunction structure consisting of the g-C_(3)N_(4)and TiO_(2)with Ti_(3)C_(2)as an electron bridge was constructed.The photocatalytic performance of the prepared catalysts was evaluated by degrading the Rhodamine B(RhB)wastewater.Compared with the single g-C_(3)N_(4),the g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)composite photocatalyst exhibited efficient and stable photocatalytic degradation ability,with a degradation efficiency as high as 99.2%for RhB under optimal conditions(2%Ti_(3)C_(2),pH=3).The high degradation performance of g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)for RhB was attributed to the combination of Ti_(3)C_(2),TiO_(2),and g-C_(3)N_(4)components,forming a direct-Z-scheme heterojunction with a high-speed electron transport channel structure.The role of Z-scheme heterojunctions in electron transport is verified by photoelectrochemical characterization,along with photoluminescence(PL).Our research provides a simple method to design photocatalysts by constructing direct-Z-scheme electron transport channels for highly efficient treatment of dye wastewater.展开更多
By using inorganic salts as raw materials and citric acid as complexing agent, α-Zn 3(PO 4) 2 and Eu 3+ doped α-Zn 3(PO 4) 2 phosphor powders were prepared by a citrate-gel process. X-ray diffraction (XRD), T...By using inorganic salts as raw materials and citric acid as complexing agent, α-Zn 3(PO 4) 2 and Eu 3+ doped α-Zn 3(PO 4) 2 phosphor powders were prepared by a citrate-gel process. X-ray diffraction (XRD), TG-DTA, FT-IR and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 ℃ and pure α-Zn 3(PO 4) 2 phase is obtained at 800 ℃. And the results of XRD reveal that Eu 3+ exists as EuPO 4 in the powder. In the phosphor powders, the Eu 3+ shows its characteristic red-orange (592 nm, 5D 0- 7F 1) emission and has no quenching concentration.展开更多
Luminescence and defect properties of novel phosphor β-Zn 3(PO 4) 2:Zr 4+ were systematically investigated. Corresponding to its lowest optical absorption transition at 240 nm, phosphor emits a bluish-green light...Luminescence and defect properties of novel phosphor β-Zn 3(PO 4) 2:Zr 4+ were systematically investigated. Corresponding to its lowest optical absorption transition at 240 nm, phosphor emits a bluish-green light at 485 nm, which yields the Stokes shift about 20000 cm -1. The unusual optical properties of Zr 4+ ion are ascribed to its uncommon coordination environment. In addition it shows intensive bluish-green long lasting phosphorescence (LLP) due to the existence of electron trap, which is generated by aliovalent substitution of Zr 4+ ion for the cation site in the matrix as shown in thermoluminescence (TL) spectrum.展开更多
One-dimensional and quasi-one-dimensional nanostructure materials are promising building blocks for electromagnetic devices and nanosystems.In this work,the composite Ni0.5Zn0.5Fe2O4（NZFO）/ Pb（Zr0.52Ti0.48）O3（PZT...One-dimensional and quasi-one-dimensional nanostructure materials are promising building blocks for electromagnetic devices and nanosystems.In this work,the composite Ni0.5Zn0.5Fe2O4（NZFO）/ Pb（Zr0.52Ti0.48）O3（PZT） nanofibers with average diameters about 65 nm are prepared by electrospinning from poly（vinyl pyrrolidone） （PVP） and metal salts.The precursor composite NZFO/PZT/PVP nanofibers and the subsequent calcined NZFO/PZT nanofibers are investigated by Fourier transform infrared spectroscopy （FT- IR） ,X-ray diffraction （XRD）,scanning electron microscopy （SEM）.The magnetic properties for nanofibers are measured by vibrating sample magnetometer（VSM）.The NZFO/PZT nanofibers obtained at calcination temperature of 900 °C for 2 h consist of the ferromagnetic spinel NZFO and ferroelectric perovskite PZT phases,which are constructed from about 37 nm NZFO and 17 nm PZT grains.The saturation magnetization of these NZFO/PZT nanofibers increases with increasing calcination temperature and contents of NZFO in the composite.展开更多
KF Zn 3(PO 4) 2 catalyst was found to be effective for isobutane oxidative dehydrogenation into isobutene. The effects of O 2 concentration in feed gas on isobutene yield and selectivity were discussed. The modi...KF Zn 3(PO 4) 2 catalyst was found to be effective for isobutane oxidative dehydrogenation into isobutene. The effects of O 2 concentration in feed gas on isobutene yield and selectivity were discussed. The modification of zinc phosphate by potassium fluoride leads to the formation of a new compound KF Zn 3(PO 4) 2 and surface basic sites, the catalytic performance of which is thus improved.展开更多
基金supported by the National Natural Science Foundation of China (No.52364022)the Natural Science Foundation of Guangxi Province,China (Nos.2023JJA160192 and 2021GXNSFAA220096)+1 种基金the Guangxi Science and Technology Major Project,China (No.AA23073018)the Guangxi Chongzuo Science and Technology Plan,China (No.2023ZY00503).
文摘With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environments, thereby endangering human health. Therefore, in this paper, a novel functionalized mesoporous adsorbent PPR-Z was synthesized from waste amidoxime resin for adsorbing Cr(Ⅵ). The waste amidoxime resin was first modified with H3PO4 and ZnCl_(2), and subsequently, it was carbonized through slow thermal decomposition. The static adsorption of PPR-Z conforms to the pseudo-second-order kinetic model and Langmuir isotherm, indicating that the Cr(Ⅵ) adsorption by PPR-Z is mostly chemical adsorption and exhibits single-layer adsorption. The saturated adsorption capacity of the adsorbent for Cr(Ⅵ) could reach 255.86 mg/g. The adsorbent could effectively reduce Cr(Ⅵ) to Cr(Ⅲ) and decrease the toxicity of Cr(Ⅵ) during adsorption. PPR-Z exhibited Cr(Ⅵ) selectivity in electroplating wastewater. The main mechanisms involved in the Cr(Ⅵ) adsorption are the chemical reduction of Cr(Ⅵ) into Cr(Ⅲ) and electrostatic and coordination interactions. Preparation of PPR-Z not only solves the problem of waste resin treatment but also effectively controls Cr(Ⅵ) pollution and realizes the concept of “treating waste with waste”.
文摘A new zinc hydrogen phosphite C4H8N2H4·Zn（HPO3）2 was prepared by hydrothermal method in the presence of piperazine as a structure-directing agent and the crystal structure was determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, IR, ICP, elemental analysis and TG analysis. This compound has one-dimensional anionic chains containing four-membered rings built from corner-sharing linked alternating ZnO4 tetrahedra and HPO3 pseudo pyramids. The zinc hydrogen phosphite chains are interacted with the templates of diprotonated piperazine by N—H…O hydrogen bond. Crystal data for C4H8N2H4·Zn（HPO3）2∶monoclinic, space group C2/c. a=1.774 8（2） nm, b=0.724 28（9） nm, c=0.880 87（11） nm, β= 105.345（3）°, V=1.091 9（2） nm 3, Z=4, Dc=1^907 Mg/m 3, R1=0.022 9, wR2=0.058 8.
基金supported by the National Natural Science Foundation of China(22078138)the Natural Science Foundation of Jiangxi Province(20202ACBL203009).
文摘Direct-Z-scheme g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)photocatalyst with giant internal electric field was prepared by onestep aqueous sonication self-assembly method using g-C_(3)N_(4)and MXene of Ti_(3)C_(2)as the source materials.The chemical composition and structure of the catalysts was characterized by FT-IR,XRD,SEM,TEM,and XPS.The XPS characterization indicated that Ti_(3)C_(2)was partially oxidized to TiO_(2)during the composite process.As a result,an efficient direct-Z-scheme heterojunction structure consisting of the g-C_(3)N_(4)and TiO_(2)with Ti_(3)C_(2)as an electron bridge was constructed.The photocatalytic performance of the prepared catalysts was evaluated by degrading the Rhodamine B(RhB)wastewater.Compared with the single g-C_(3)N_(4),the g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)composite photocatalyst exhibited efficient and stable photocatalytic degradation ability,with a degradation efficiency as high as 99.2%for RhB under optimal conditions(2%Ti_(3)C_(2),pH=3).The high degradation performance of g-C_(3)N_(4)/Ti_(3)C_(2)/TiO_(2)for RhB was attributed to the combination of Ti_(3)C_(2),TiO_(2),and g-C_(3)N_(4)components,forming a direct-Z-scheme heterojunction with a high-speed electron transport channel structure.The role of Z-scheme heterojunctions in electron transport is verified by photoelectrochemical characterization,along with photoluminescence(PL).Our research provides a simple method to design photocatalysts by constructing direct-Z-scheme electron transport channels for highly efficient treatment of dye wastewater.
文摘By using inorganic salts as raw materials and citric acid as complexing agent, α-Zn 3(PO 4) 2 and Eu 3+ doped α-Zn 3(PO 4) 2 phosphor powders were prepared by a citrate-gel process. X-ray diffraction (XRD), TG-DTA, FT-IR and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 ℃ and pure α-Zn 3(PO 4) 2 phase is obtained at 800 ℃. And the results of XRD reveal that Eu 3+ exists as EuPO 4 in the powder. In the phosphor powders, the Eu 3+ shows its characteristic red-orange (592 nm, 5D 0- 7F 1) emission and has no quenching concentration.
基金supported by the Natural Science Foundation of Hebei Province,China(B2014209182)Youth Foundation of Hebei Education Department,China(QN2014045)College Students'Innovative Entrepreneurial Training Plan Program of North China University of Science and Technology,China(X2015117)~~
文摘水热法结合原位沉淀法成功制备新型磁性溴化银/磷酸银/铁酸锌(AgBr/Ag_3PO_4/ZnFe_2O_4)复合催化剂,并通过X射线衍射、能量色散X射线、场发射扫描电子显微镜、透射电子显微镜和紫外-可见漫反射光谱对其晶相结构、组成、形貌及吸光性能进行了表征。在可见光照射下,所制备的AgBr/Ag_3PO_4/ZnFe_2O_4复合催化剂光催化降解罗丹明B(RhB)的活性优于Ag_3PO_4/ZnFe_2O_4、AgBr/ZnFe_2O_4和P25 TiO_2。在酸性和碱性溶液中,AgBr/Ag_3PO_4/ZnFe_2O_4光催化剂呈现出优良光催化性能。在AgBr/Ag_3PO_4/ZnFe_2O_4体系中,光催化降解Rh B的速率随着反应体系温度的升高而增大,由阿伦尼乌斯方程计算获得反应体系活化能为31.9 k J?mol^(-1)。AgBr/Ag_3PO_4/ZnFe_2O_4复合材料优异的可见光催化活性归因于光生电荷的有效分离,所产生的超氧自由基和空穴是Rh B降解的主要活性物种。
文摘Luminescence and defect properties of novel phosphor β-Zn 3(PO 4) 2:Zr 4+ were systematically investigated. Corresponding to its lowest optical absorption transition at 240 nm, phosphor emits a bluish-green light at 485 nm, which yields the Stokes shift about 20000 cm -1. The unusual optical properties of Zr 4+ ion are ascribed to its uncommon coordination environment. In addition it shows intensive bluish-green long lasting phosphorescence (LLP) due to the existence of electron trap, which is generated by aliovalent substitution of Zr 4+ ion for the cation site in the matrix as shown in thermoluminescence (TL) spectrum.
基金Funded by the National Natural Science Foundation of China (No. 50674048)Research Fund for the Doctoral Program of Higher Education of China(No.20103227110006)
文摘One-dimensional and quasi-one-dimensional nanostructure materials are promising building blocks for electromagnetic devices and nanosystems.In this work,the composite Ni0.5Zn0.5Fe2O4（NZFO）/ Pb（Zr0.52Ti0.48）O3（PZT） nanofibers with average diameters about 65 nm are prepared by electrospinning from poly（vinyl pyrrolidone） （PVP） and metal salts.The precursor composite NZFO/PZT/PVP nanofibers and the subsequent calcined NZFO/PZT nanofibers are investigated by Fourier transform infrared spectroscopy （FT- IR） ,X-ray diffraction （XRD）,scanning electron microscopy （SEM）.The magnetic properties for nanofibers are measured by vibrating sample magnetometer（VSM）.The NZFO/PZT nanofibers obtained at calcination temperature of 900 °C for 2 h consist of the ferromagnetic spinel NZFO and ferroelectric perovskite PZT phases,which are constructed from about 37 nm NZFO and 17 nm PZT grains.The saturation magnetization of these NZFO/PZT nanofibers increases with increasing calcination temperature and contents of NZFO in the composite.
文摘KF Zn 3(PO 4) 2 catalyst was found to be effective for isobutane oxidative dehydrogenation into isobutene. The effects of O 2 concentration in feed gas on isobutene yield and selectivity were discussed. The modification of zinc phosphate by potassium fluoride leads to the formation of a new compound KF Zn 3(PO 4) 2 and surface basic sites, the catalytic performance of which is thus improved.
