Simazine and propazine are selective triazine herbicides currently in use to control broad-leaved weeds and annual grasses around the world. Bisphenol A (BPA) is an industrial chemical used in the production of polyca...Simazine and propazine are selective triazine herbicides currently in use to control broad-leaved weeds and annual grasses around the world. Bisphenol A (BPA) is an industrial chemical used in the production of polycarbonate plastics often found in consumer goods, such as plastic containers, baby bottles etc. These synthetic compounds are known to increase the risk of cancer, cause adverse reproductive effect in reptiles, mammals, birds, humans, and lead to other health problems. They have become some of the principal agents of contamination in water bodies around the world through herbicide runoff, industrial waste and leaching. Some triazines such as atrazine are banned in most European countries for over ten years due to their adverse reproductive effect in mammals, birds and humans;however propazine and simazine are still in use around the world. The removal of these compounds from contaminated water is an exigent challenge. In this study, we investigated their affinity for the surface of nanoparticles (NPS) and standard metallic oxides in an effort to exploit the unique potential applications of NPS for water purification systems. We studied the adsorption of the two triazines and BPA on the surface of NPS of iron (III) oxide, NPS of carbon, bulk iron (III) oxide and aluminum oxide at pH 6 and pH 8 using UV-Visible spectroscopy. Result indicates that these compounds have different affinity towards the surface of metallic oxides and carbon at various pHs. In general, there is relatively high adsorption of some of these compounds on the surface of NPS compared to bulk particles. NPS of carbon have shown the highest affinity for all the three compounds. The lower pH was found to be favorable for all of the compounds except for BPA. BPA have shown high adsorption at pH 8 than at pH 6.展开更多
This paper presents the preparation of carbon conditioned with iron nanoparticles (CI) using a pineapple peel treated with iron salts, carboxymethylcellulose sodium and hexamine. First, the pineapple peel was analyzed...This paper presents the preparation of carbon conditioned with iron nanoparticles (CI) using a pineapple peel treated with iron salts, carboxymethylcellulose sodium and hexamine. First, the pineapple peel was analyzed by thermo gravimetric analysis (TGA) to determine the optimal temperature for pyrolysis. The formation of carbon conditioned by iron nanoparticles was studied as a function of time at 30 min, 60 min, 90 min, 120 min, 150 min and 180 min. Scanning electron microscopy (SEM) was used to identify changes in the morphology of the materials. The specific area of each material was obtained by the BET method. The elemental composition of pineapple-peel (PP), washed pineapple-peel (WPP) and carbon iron (CI), was determined by neutron activation analysis (NAA). The results show that the optimal time for obtaining spherical iron nanoparticles with a diameter between 10 nm and 30 nm is 180 min on the carbonaceous material with a specific surface area of 167 m2/g.展开更多
Carbon encapsulated iron nanoparticles （CEINPs） with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature （AIT） of 800 ℃. The results of high resolution tr...Carbon encapsulated iron nanoparticles （CEINPs） with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature （AIT） of 800 ℃. The results of high resolution transmission electron microscope （HRTEM）, energy dispersive X-ray （EDX） spectroscope, X-ray diffraction （XRD）, and X-ray photoelectron spectroscope （XPS） characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5-5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization （Ms） and coercivity （Hc） of the product B are 107.4 emu/g and 143 Oe. resnectivelv. The formation of the CEINPs in the oroduct B is discussed briefly.展开更多
Core-shell nanoparticles Fe@Fe3O4 supported on activated carbon (AC) and carbon nanotubes (CNTs) have been studied by H2 temperature-programmed reduction (TPR). Nanoparticles with size of 6.5 nm were synthesized by ir...Core-shell nanoparticles Fe@Fe3O4 supported on activated carbon (AC) and carbon nanotubes (CNTs) have been studied by H2 temperature-programmed reduction (TPR). Nanoparticles with size of 6.5 nm were synthesized by iron(II) oleate thermal decomposition and were supported on activated carbon and carbon nanotubes by colloid deposition method. The nanoparticles Fe@Fe3O4 are characterized by TEM and IR. Reduction of nanoparticles on AC starts at 140?C, whereas reduction of nanoparticles on CNTs starts at 200?C. Moreover, gasification of CNTs with methane releasing starts at 450?C, whereas gasification of AC is negligible at temperatures up to 800?C. All these findings illustrate a strong difference in the interaction between nanoparticles and the support material for AC and CNTs.展开更多
The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunc...The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunctional architecture to manipulate the redox kinetics of polysulfides,specifically,by employing iron atoms(Fe-As)and iron-species nanoparticles(Fe-NPs)co-embedded nitrogen-doped carbon nanotube(Fe-NCNT)as catalyst and host for sulfur.The synergistic cooperation of Fe-As and Fe-NPs provides efficient active sites to facilitate the diffusion,strengthen the affinities,and promote the conversion reactions for polysulfides.Furthermore,the NCNT not only offers practical Li+transport pathways but also immobilize the polysulfides effectively.Benefiting from these merits,the Fe-NCNT/S electrodes exhibit high initial specific capacity of 1502.6 mAh/g at 0.1 C,outstanding rate performance(830 mAh/g at 2 C),and good cycling performance(597.8 mAh/g after 500 cycles with an ultralow capacity fading rate of 0.069%per cycle).This work features the distinct interaction of iron atom-nanoparticles on facilitating immobilization-diffusion-transformation process of polysulfides,and it also expected to pave the way for the application in practical Li-S batteries.展开更多
Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles（CNPs） ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which t...Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles（CNPs） ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which the nitrogen and sulfur co-doping improves the photoluminescent efficiency of the CNPs. The as-prepared CNPs display excellent fluorescent properties and low biotoxicity with a relatively high quantum yield of 30.4%, which have been applied for bioimaging and highly sensitive and selective detection of iron（III） ions.展开更多
文摘Simazine and propazine are selective triazine herbicides currently in use to control broad-leaved weeds and annual grasses around the world. Bisphenol A (BPA) is an industrial chemical used in the production of polycarbonate plastics often found in consumer goods, such as plastic containers, baby bottles etc. These synthetic compounds are known to increase the risk of cancer, cause adverse reproductive effect in reptiles, mammals, birds, humans, and lead to other health problems. They have become some of the principal agents of contamination in water bodies around the world through herbicide runoff, industrial waste and leaching. Some triazines such as atrazine are banned in most European countries for over ten years due to their adverse reproductive effect in mammals, birds and humans;however propazine and simazine are still in use around the world. The removal of these compounds from contaminated water is an exigent challenge. In this study, we investigated their affinity for the surface of nanoparticles (NPS) and standard metallic oxides in an effort to exploit the unique potential applications of NPS for water purification systems. We studied the adsorption of the two triazines and BPA on the surface of NPS of iron (III) oxide, NPS of carbon, bulk iron (III) oxide and aluminum oxide at pH 6 and pH 8 using UV-Visible spectroscopy. Result indicates that these compounds have different affinity towards the surface of metallic oxides and carbon at various pHs. In general, there is relatively high adsorption of some of these compounds on the surface of NPS compared to bulk particles. NPS of carbon have shown the highest affinity for all the three compounds. The lower pH was found to be favorable for all of the compounds except for BPA. BPA have shown high adsorption at pH 8 than at pH 6.
文摘This paper presents the preparation of carbon conditioned with iron nanoparticles (CI) using a pineapple peel treated with iron salts, carboxymethylcellulose sodium and hexamine. First, the pineapple peel was analyzed by thermo gravimetric analysis (TGA) to determine the optimal temperature for pyrolysis. The formation of carbon conditioned by iron nanoparticles was studied as a function of time at 30 min, 60 min, 90 min, 120 min, 150 min and 180 min. Scanning electron microscopy (SEM) was used to identify changes in the morphology of the materials. The specific area of each material was obtained by the BET method. The elemental composition of pineapple-peel (PP), washed pineapple-peel (WPP) and carbon iron (CI), was determined by neutron activation analysis (NAA). The results show that the optimal time for obtaining spherical iron nanoparticles with a diameter between 10 nm and 30 nm is 180 min on the carbonaceous material with a specific surface area of 167 m2/g.
文摘Carbon encapsulated iron nanoparticles （CEINPs） with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature （AIT） of 800 ℃. The results of high resolution transmission electron microscope （HRTEM）, energy dispersive X-ray （EDX） spectroscope, X-ray diffraction （XRD）, and X-ray photoelectron spectroscope （XPS） characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5-5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization （Ms） and coercivity （Hc） of the product B are 107.4 emu/g and 143 Oe. resnectivelv. The formation of the CEINPs in the oroduct B is discussed briefly.
文摘Core-shell nanoparticles Fe@Fe3O4 supported on activated carbon (AC) and carbon nanotubes (CNTs) have been studied by H2 temperature-programmed reduction (TPR). Nanoparticles with size of 6.5 nm were synthesized by iron(II) oleate thermal decomposition and were supported on activated carbon and carbon nanotubes by colloid deposition method. The nanoparticles Fe@Fe3O4 are characterized by TEM and IR. Reduction of nanoparticles on AC starts at 140?C, whereas reduction of nanoparticles on CNTs starts at 200?C. Moreover, gasification of CNTs with methane releasing starts at 450?C, whereas gasification of AC is negligible at temperatures up to 800?C. All these findings illustrate a strong difference in the interaction between nanoparticles and the support material for AC and CNTs.
基金supported by the Natural Science Foundation of China(Nos.22125902,U2032202,21975243 and 21825302)the National Program for Support of Topnotch Young Professionals,the Fundamental Research Funds for the Central Universities(No.WK2030020032)+1 种基金the DNL cooperation Fund,CAS(No.DNL202020)the Anhui Science Fund for Distinguished Young Scholars(No.2208085J15).
文摘The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunctional architecture to manipulate the redox kinetics of polysulfides,specifically,by employing iron atoms(Fe-As)and iron-species nanoparticles(Fe-NPs)co-embedded nitrogen-doped carbon nanotube(Fe-NCNT)as catalyst and host for sulfur.The synergistic cooperation of Fe-As and Fe-NPs provides efficient active sites to facilitate the diffusion,strengthen the affinities,and promote the conversion reactions for polysulfides.Furthermore,the NCNT not only offers practical Li+transport pathways but also immobilize the polysulfides effectively.Benefiting from these merits,the Fe-NCNT/S electrodes exhibit high initial specific capacity of 1502.6 mAh/g at 0.1 C,outstanding rate performance(830 mAh/g at 2 C),and good cycling performance(597.8 mAh/g after 500 cycles with an ultralow capacity fading rate of 0.069%per cycle).This work features the distinct interaction of iron atom-nanoparticles on facilitating immobilization-diffusion-transformation process of polysulfides,and it also expected to pave the way for the application in practical Li-S batteries.
基金financial supports of the National Natural Science Foundation of China(No.21535006)the Fundamental Research Funds for the Central Universities(No.XDJK2015B029)
文摘Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles（CNPs） ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which the nitrogen and sulfur co-doping improves the photoluminescent efficiency of the CNPs. The as-prepared CNPs display excellent fluorescent properties and low biotoxicity with a relatively high quantum yield of 30.4%, which have been applied for bioimaging and highly sensitive and selective detection of iron（III） ions.
基金supported by the National Natural Science Foundation of China(21321002 and 21303191)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA09030100)~~
