Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bon...Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts.展开更多
Global warming and associated global climate change have led to serious efforts towards reducing CO_(2)emissions through the CO_(2)capture from the major emission sources.CO_(2)capture using the amine functionalized a...Global warming and associated global climate change have led to serious efforts towards reducing CO_(2)emissions through the CO_(2)capture from the major emission sources.CO_(2)capture using the amine functionalized adsorbents is regard as a direct and effective way to reducing CO_(2)emissions due to their large CO_(2)adsorption amount,excellent CO_(2)adsorption selectivity and lower energy requirements for adsorbent regeneration.Moreover,large number of achievements on the amine functionalized solid adsorbent have been recorded for the enhanced CO_(2)capture in the past few years.In view of this,we review and analyze the recent advances in amine functionalized solid adsorbents prepared with different supporting materials including mesoporous silica,zeolite,porous carbon materials,metal organic frameworks(MOF)and other composite porous materials.In addition,amine functionalized solid adsorbents derived from waste resources are also reviewed because of the large number demand for cost-effective carbon dioxide adsorbents and the processing needs of waste resources.Considering the importance of the stability of the adsorbent in practical applications,advanced research in the capture cycle stability has also been summarized and analyzed.Finally,we summarize the review and offer the recommendations for the development of amine-based solid adsorbents for carbon dioxide capture.展开更多
A review of methods for the anionic synthesis of well-defined, amine-functionalized polymers using imines as functionalizing agents is provided. The disparate results in the literature regarding functionalizations wit...A review of methods for the anionic synthesis of well-defined, amine-functionalized polymers using imines as functionalizing agents is provided. The disparate results in the literature regarding functionalizations with N -(benzylidene)trimethylsilylamine to form primary amine functionalized polymers are discussed; the efficiency of functionalization depends on the molecular weight of the polymeric organolithium(PLi). Efficient functionalizations are observed for PLi with n>10 000 g/mol. The poor functionalization yields using ketimines with enolizable hydrogens is explained. The use of N -trimethylsilyldiphenylcarbimide as a quantitative primary amine functionalizing reagent is described. Recent results on the anionic synthesis of secondary amine-functionalized polymers using N -(benzylidene)methylamine as the functionalization agent are presented.展开更多
Palladium nanoparticles were deposited on the amine-grafted glass fiber mat (GFM-NH2) catalyst support by a conventional impregnation process followed by the borohydride reduction in aqueous solution at room tempera...Palladium nanoparticles were deposited on the amine-grafted glass fiber mat (GFM-NH2) catalyst support by a conventional impregnation process followed by the borohydride reduction in aqueous solution at room temperature to create the designed Pd/GFM-NH2 catalyst. By the use of large size glass fiber mat without nano/mesopores as the catalyst support, the internal mass transfer limitations due to the existence of nano/mesopores on the catalyst support were eliminated and the Pd/GFM-NH2 catalyst could be easily separated from treated water due to the large size of the catalyst support. Batch experiments demonstrate its good catalytic reduction performance of Cr(VI) with formic acid as the reducing agent. It also demonstrated an efficient Cr(VI) removal and stability in a lab-prepared, packed fixed-bed tube reactor for the continuous treatment of Cr(VI)-containing water. Thus, it has a good potential for the catalytic reduction of Cr(VI) in the water treatment practice.展开更多
Recently, many attempts have been made to use carbon nanotubes in analytical chemistry, especially in adsorption of heavy metal ions from water. In this study, multiwalled carbon nanotubes (MWCNTs) were functionalized...Recently, many attempts have been made to use carbon nanotubes in analytical chemistry, especially in adsorption of heavy metal ions from water. In this study, multiwalled carbon nanotubes (MWCNTs) were functionalized with tris(2-aminoethyl) amine. The functionalized nanoparticles were characterized using Fourier transform infrared (FTIR), thermal gravimetric analyzer (TGA), elemental analysis, and Raman spectroscopy. The results revealed that the functionalization reaction was successfully accomplished. Lead adsorption from water was carried out using functionalized MWCNTs and measured by flame atomic absorption spectrometry (FAAS). The effects of pH, shaking time, initial metal ion concentration, and adsorbent dosage on the adsorption process were studied via batch method. The results obtained showed that removal of lead ions strongly depended on the pH. Desorption study revealed that lead ions adsorbed on the functionalized MWCNTs could be desorbed at pH 3 due to breakage of complexes formed on the sorbent surface. Maximum adsorption capacity of the sorbent under the optimal conditions was 43 mg/g. This favorable adsorption capacity suggests that functionalized carbon nanotubes can be applied for removal of lead from water solutions. The data obtained were fitted with the Langmuir and Freundlich isotherm adsorption models and Langmuir model showed better agreement with the experimental data.展开更多
Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from t...Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.展开更多
Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) ...Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) (PVA) at 90 degree C and act as plasticizer in the blend films cast from the solution. Only a glass transition temperature is observed for all these blends indicating the formation of compatible blends from these polyesters with PVA. These blends exhibit manifold characteristics such as ionic conductivity, complex formation with metal ions, absorption of moisture and color changes. The electric conductivity of the copolyesters and blends is in the range of 10** minus **6 Scm** minus **1. The blends with PVA forms complexes with Cu**2** plus and Co**2** plus . The coordination structure with two chelate rings is suggested for these polymer blend/metal complexes. (Author abstract) 10 Refs.展开更多
基金supported by the National Natural Science Foundation of China(No.62304219)the Strategic Priority Research Program of theChinese Academy of Sciences(No.XDB43000000)+1 种基金the CAS Project for Young Scientists in Basic Research(YSBR−090)the National Natural ScienceFoundation of China(Nos.21975245,U20A20206,and 51972300)。
文摘Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts.
基金supported by the National Natural Science Foundation of China(21878200 and 21676174)International S&T Cooperation Program of Shanxi province(201703D421038)+1 种基金Shanxi Scholarship Council of China(2017-036)Joint Fund of Shanxi Provincial Coal Seam Gas(2015012019)。
文摘Global warming and associated global climate change have led to serious efforts towards reducing CO_(2)emissions through the CO_(2)capture from the major emission sources.CO_(2)capture using the amine functionalized adsorbents is regard as a direct and effective way to reducing CO_(2)emissions due to their large CO_(2)adsorption amount,excellent CO_(2)adsorption selectivity and lower energy requirements for adsorbent regeneration.Moreover,large number of achievements on the amine functionalized solid adsorbent have been recorded for the enhanced CO_(2)capture in the past few years.In view of this,we review and analyze the recent advances in amine functionalized solid adsorbents prepared with different supporting materials including mesoporous silica,zeolite,porous carbon materials,metal organic frameworks(MOF)and other composite porous materials.In addition,amine functionalized solid adsorbents derived from waste resources are also reviewed because of the large number demand for cost-effective carbon dioxide adsorbents and the processing needs of waste resources.Considering the importance of the stability of the adsorbent in practical applications,advanced research in the capture cycle stability has also been summarized and analyzed.Finally,we summarize the review and offer the recommendations for the development of amine-based solid adsorbents for carbon dioxide capture.
文摘A review of methods for the anionic synthesis of well-defined, amine-functionalized polymers using imines as functionalizing agents is provided. The disparate results in the literature regarding functionalizations with N -(benzylidene)trimethylsilylamine to form primary amine functionalized polymers are discussed; the efficiency of functionalization depends on the molecular weight of the polymeric organolithium(PLi). Efficient functionalizations are observed for PLi with n>10 000 g/mol. The poor functionalization yields using ketimines with enolizable hydrogens is explained. The use of N -trimethylsilyldiphenylcarbimide as a quantitative primary amine functionalizing reagent is described. Recent results on the anionic synthesis of secondary amine-functionalized polymers using N -(benzylidene)methylamine as the functionalization agent are presented.
基金supported by the Basic Science Innovation Program of Shenyang National Laboratory for Materials Science(Grant Nos.Y4N56R1161 and Y4N56F2161)the National Natural Science Foundation of China(Grant No.51502305)
文摘Palladium nanoparticles were deposited on the amine-grafted glass fiber mat (GFM-NH2) catalyst support by a conventional impregnation process followed by the borohydride reduction in aqueous solution at room temperature to create the designed Pd/GFM-NH2 catalyst. By the use of large size glass fiber mat without nano/mesopores as the catalyst support, the internal mass transfer limitations due to the existence of nano/mesopores on the catalyst support were eliminated and the Pd/GFM-NH2 catalyst could be easily separated from treated water due to the large size of the catalyst support. Batch experiments demonstrate its good catalytic reduction performance of Cr(VI) with formic acid as the reducing agent. It also demonstrated an efficient Cr(VI) removal and stability in a lab-prepared, packed fixed-bed tube reactor for the continuous treatment of Cr(VI)-containing water. Thus, it has a good potential for the catalytic reduction of Cr(VI) in the water treatment practice.
文摘Recently, many attempts have been made to use carbon nanotubes in analytical chemistry, especially in adsorption of heavy metal ions from water. In this study, multiwalled carbon nanotubes (MWCNTs) were functionalized with tris(2-aminoethyl) amine. The functionalized nanoparticles were characterized using Fourier transform infrared (FTIR), thermal gravimetric analyzer (TGA), elemental analysis, and Raman spectroscopy. The results revealed that the functionalization reaction was successfully accomplished. Lead adsorption from water was carried out using functionalized MWCNTs and measured by flame atomic absorption spectrometry (FAAS). The effects of pH, shaking time, initial metal ion concentration, and adsorbent dosage on the adsorption process were studied via batch method. The results obtained showed that removal of lead ions strongly depended on the pH. Desorption study revealed that lead ions adsorbed on the functionalized MWCNTs could be desorbed at pH 3 due to breakage of complexes formed on the sorbent surface. Maximum adsorption capacity of the sorbent under the optimal conditions was 43 mg/g. This favorable adsorption capacity suggests that functionalized carbon nanotubes can be applied for removal of lead from water solutions. The data obtained were fitted with the Langmuir and Freundlich isotherm adsorption models and Langmuir model showed better agreement with the experimental data.
基金supported by the Shanghai Agricultural Science and Technology Program (2022-02-08-00-12-F01176)he National Natural Science Foundation of China (52006135)
文摘Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.
文摘Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) (PVA) at 90 degree C and act as plasticizer in the blend films cast from the solution. Only a glass transition temperature is observed for all these blends indicating the formation of compatible blends from these polyesters with PVA. These blends exhibit manifold characteristics such as ionic conductivity, complex formation with metal ions, absorption of moisture and color changes. The electric conductivity of the copolyesters and blends is in the range of 10** minus **6 Scm** minus **1. The blends with PVA forms complexes with Cu**2** plus and Co**2** plus . The coordination structure with two chelate rings is suggested for these polymer blend/metal complexes. (Author abstract) 10 Refs.