A new two dimensional 8 ring network nickle phosphate Ni 3(PO 4) 2·8H 2O was synthesized hydrothermally and its structure was determined by means of single crystal X ray diffraction. The Ni 3(PO 4) 2·8H 2O c...A new two dimensional 8 ring network nickle phosphate Ni 3(PO 4) 2·8H 2O was synthesized hydrothermally and its structure was determined by means of single crystal X ray diffraction. The Ni 3(PO 4) 2·8H 2O crystal crystallizes in the monoclinic system, space group C2/m , with M=128.13, a =0\^994 7(2) nm, b =1.321 7(3) nm; c =0.463 6(1) nm; β=104.80(3)°, V =0.589 3(2) nm 3, Z=2, R=0.027 2 and wR =0.057 5. The network structure consists of vertex sharing which results in the formation of undulating 4 ring chains and 8 ring sheets.展开更多
Series of heterogeneous interfacial engineered TiO2(C-TiO2) with controllable carbon content were facilely synthesized by incipient-wet impregnation using glucose and subsequent thermal carbonization. The obtained C-T...Series of heterogeneous interfacial engineered TiO2(C-TiO2) with controllable carbon content were facilely synthesized by incipient-wet impregnation using glucose and subsequent thermal carbonization. The obtained C-TiO2 were used as catalytic supports to load Pd nanoparticles for H2 O2 direct synthesis from H2 and O2. The as-prepared samples were systematically studied by transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), air isothermal microcalorimeter, temperature-programmed reduction of H2(H2-TPR), and so on. The catalytic results showed that H2 O2 productivity and H2O2 selectivity of Pd/C-TiO2 firstly rose with increasing carbon content and then declined. Pd/C-TiO2 catalyst with 1.89 wt% of carbon content showed the best catalytic performance that had 61.2% of selectivity and 2192 mmol H2O2/g Pd/h of productivity, which were significantly better than those of pristine Pd/TiO2(45.2% and 1827 mmol H2O2/g Pd/h). Various characterization results displayed that the carbon species were heterogeneously dispersed on TiO2 surface. Moreover, no obvious geometric transformation in supports and Pd nanoparticles were observed among different catalysts. The superficial hydrophobicity of Pd/C-TiO2 was gradually promoted with increasing carbon content, which led to the corresponding decrease in adsorption energy of H2O2 with catalysts. According to structure-performance relationship analyses, the heterogeneous interfacial engineering of carbon could maintain the interaction of Pd nanoparticles with TiO2 and simultaneously accelerate the H2O2 desorption. Both factors further determined the excellent H2O2 direct synthesis performance of Pd/C-TiO2.展开更多
The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized con...The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized conditions,the cyclohexanone conversion and 6-hydroxyhexanoic acid selectivity are over 95%, respectively. The excellent catalyticperformance is attributed to the activation of carbonyl group of cyclohexanone and the fast hydrolysis and ring opening ofs-caprolactone by both Lewis acid and Br0nsted acid sites under aqueous conditions.展开更多
The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation...The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.展开更多
Polyoxomolybdate [Mo36O110（NO）4（H2O）14].52H2O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na2MoO4.2H2O and NH2OH. HCl. In order to create a heterogeneous catalyst system,...Polyoxomolybdate [Mo36O110（NO）4（H2O）14].52H2O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na2MoO4.2H2O and NH2OH. HCl. In order to create a heterogeneous catalyst system, the polyoxomolybdate was pillared with MgAI-LDH-NO3 by direct ion exchange. These novel materials were carefully analyzed by various chemico-physical methods, The catalytic degradation of methylene blue （MB） and rhodamine B （RB） as common dyes in the presence of MgAl-LDH-1 nanoparticles with aqueous hydrogen peroxide, H2O2, as an oxidizing agent was studied in aqueous solution at room temperature. More importantly, the catalyst can be recovered and reused efficiently up to five consecutive cycles with negligible loss of catalytic activity.展开更多
文摘A new two dimensional 8 ring network nickle phosphate Ni 3(PO 4) 2·8H 2O was synthesized hydrothermally and its structure was determined by means of single crystal X ray diffraction. The Ni 3(PO 4) 2·8H 2O crystal crystallizes in the monoclinic system, space group C2/m , with M=128.13, a =0\^994 7(2) nm, b =1.321 7(3) nm; c =0.463 6(1) nm; β=104.80(3)°, V =0.589 3(2) nm 3, Z=2, R=0.027 2 and wR =0.057 5. The network structure consists of vertex sharing which results in the formation of undulating 4 ring chains and 8 ring sheets.
基金supported by the National Natural Science Foundation of China(21878143,21476106,21838004)Joint Re-search Fund for Overseas Chinese Scholars and Scholars in Hong Kong and Macao Young Scholars(21729601)+1 种基金the fund of State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201702)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)~~
文摘Series of heterogeneous interfacial engineered TiO2(C-TiO2) with controllable carbon content were facilely synthesized by incipient-wet impregnation using glucose and subsequent thermal carbonization. The obtained C-TiO2 were used as catalytic supports to load Pd nanoparticles for H2 O2 direct synthesis from H2 and O2. The as-prepared samples were systematically studied by transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), air isothermal microcalorimeter, temperature-programmed reduction of H2(H2-TPR), and so on. The catalytic results showed that H2 O2 productivity and H2O2 selectivity of Pd/C-TiO2 firstly rose with increasing carbon content and then declined. Pd/C-TiO2 catalyst with 1.89 wt% of carbon content showed the best catalytic performance that had 61.2% of selectivity and 2192 mmol H2O2/g Pd/h of productivity, which were significantly better than those of pristine Pd/TiO2(45.2% and 1827 mmol H2O2/g Pd/h). Various characterization results displayed that the carbon species were heterogeneously dispersed on TiO2 surface. Moreover, no obvious geometric transformation in supports and Pd nanoparticles were observed among different catalysts. The superficial hydrophobicity of Pd/C-TiO2 was gradually promoted with increasing carbon content, which led to the corresponding decrease in adsorption energy of H2O2 with catalysts. According to structure-performance relationship analyses, the heterogeneous interfacial engineering of carbon could maintain the interaction of Pd nanoparticles with TiO2 and simultaneously accelerate the H2O2 desorption. Both factors further determined the excellent H2O2 direct synthesis performance of Pd/C-TiO2.
基金supported by the National Basic Research Program of China(973 Program,2006CB202508)the China Petrochemical Corporation Program(SINOPEC Group ST417004)the National Key Research and Development Program of China(2017YFB0306800)
文摘The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized conditions,the cyclohexanone conversion and 6-hydroxyhexanoic acid selectivity are over 95%, respectively. The excellent catalyticperformance is attributed to the activation of carbonyl group of cyclohexanone and the fast hydrolysis and ring opening ofs-caprolactone by both Lewis acid and Br0nsted acid sites under aqueous conditions.
基金Supported by the National Key Basic Research Program of China(2013CB733505,2013CB733501)the National Natural Science Foundation of China(91334202)+2 种基金the Natural Science Foundation of Jiangsu Province of China(BK2012421,BK20130062)the Research Fund for the Doctoral Program of Higher Education of China(20123221120015)the Project for Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.
基金Supported by the Iranian National Science Foundation(INSF)and University of Maragheh
文摘Polyoxomolybdate [Mo36O110（NO）4（H2O）14].52H2O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na2MoO4.2H2O and NH2OH. HCl. In order to create a heterogeneous catalyst system, the polyoxomolybdate was pillared with MgAI-LDH-NO3 by direct ion exchange. These novel materials were carefully analyzed by various chemico-physical methods, The catalytic degradation of methylene blue （MB） and rhodamine B （RB） as common dyes in the presence of MgAl-LDH-1 nanoparticles with aqueous hydrogen peroxide, H2O2, as an oxidizing agent was studied in aqueous solution at room temperature. More importantly, the catalyst can be recovered and reused efficiently up to five consecutive cycles with negligible loss of catalytic activity.
