Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones ...Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired support.The synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated nanoparticles.For bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to H2.It was found that Pd-Rh molar ratio strongly influences the catalytic performance.Pd-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling tests.Finally,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.展开更多
Trimethylphenol is an organic toxic byproduct of industrial process,which is difficult to be eliminated through conventional degradation without harsh conditions.In this work,a sulfite-based oxidation process activate...Trimethylphenol is an organic toxic byproduct of industrial process,which is difficult to be eliminated through conventional degradation without harsh conditions.In this work,a sulfite-based oxidation process activated by ZnO-embedded hydrogel was studied for the degradation of 2,4,6-trimethylphenols in the ambient conditions.The ZnO/Na_(2)SO_(3)oxidative system can effectively degrade trimethylphenol via the generation of radicals such as SO_(4)^(-)·,OH·,and SO_(3)^(−)·.The presence of hydrogel matrix facilitates the distribution and recyclability of ZnO catalysts while maintaining high degradation kinetics and little leaching of metal ions.Results suggest the promising potential of ZnO-hydrogel in wastewater treatment with good performance in terms of pH sensitivity,anion interference,recyclability,etc.The combination of ZnO catalysts,hydrogel,and sulfite-based advanced oxidation process may provide essential support for the current treatment of alkylated phenols with strong potential in the commercial scale-ups.展开更多
We report the electrosynthesis of a novel semiconductor polymer based on alkyl vinylthiophene derivative in the presence of an ionic liquid (IL). The polymerization was performed under galvanostatic conditions and the...We report the electrosynthesis of a novel semiconductor polymer based on alkyl vinylthiophene derivative in the presence of an ionic liquid (IL). The polymerization was performed under galvanostatic conditions and the polymer was studied as potential donor component of a multilayer heterojunction organic solar cell (OSC). The monomer used was (E)-1,2-di-(3-octyl-2-thienyl) vinylene (OTV) and the IL used for the electropolymerization was 1-octyl-3-methylimidazole hexafluorophosphate C8mimPF6. Optical properties, stability and morphology of the polymer were analyzed using FT-IR, UV-vis, Raman and XPS spectroscopy. Voltammetry analysis and scanning electron microscopy (SEM-EDX) were also performed on the polymer. The OSC assembled with the polymer of OTV was used as electro donor and C60 as acceptor. Molybdenum trioxide (MoO3) and bathocuproine (BCP) were used as buffer layer between anode and cathode respectively. I-V curves, in the dark and under AM 1.5 solar simulator were performed to measure its efficiency.展开更多
文摘Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired support.The synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated nanoparticles.For bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to H2.It was found that Pd-Rh molar ratio strongly influences the catalytic performance.Pd-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling tests.Finally,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.
基金the Natural Science Foundation of Shandong Province(No.ZR2017LB028)the Key Research and Development Program of Shandong Province(Nos.2018GSF118032 and 2022CXGC020415)the Fundamental Research Funds for the Central Universities in China(No.18CX02125A).Y.X.L.is grateful for the Research Subsidy Funds of Marine Science Research Institute of Shandong Province.X.W.C.is grateful for Ministry of Science,Innovation and Universities of Spain with project reference number of PID2020-113809RBC33 and by Junta de Andalucía(Spain)with reference number of PY18-2727.
文摘Trimethylphenol is an organic toxic byproduct of industrial process,which is difficult to be eliminated through conventional degradation without harsh conditions.In this work,a sulfite-based oxidation process activated by ZnO-embedded hydrogel was studied for the degradation of 2,4,6-trimethylphenols in the ambient conditions.The ZnO/Na_(2)SO_(3)oxidative system can effectively degrade trimethylphenol via the generation of radicals such as SO_(4)^(-)·,OH·,and SO_(3)^(−)·.The presence of hydrogel matrix facilitates the distribution and recyclability of ZnO catalysts while maintaining high degradation kinetics and little leaching of metal ions.Results suggest the promising potential of ZnO-hydrogel in wastewater treatment with good performance in terms of pH sensitivity,anion interference,recyclability,etc.The combination of ZnO catalysts,hydrogel,and sulfite-based advanced oxidation process may provide essential support for the current treatment of alkylated phenols with strong potential in the commercial scale-ups.
基金financially supported by the FONDECYT(Project No.11100284)the Metallurgy Department of University of Atacama for the XRD and SEM analysis(Projects EQM130125 and EQUV 003)
文摘We report the electrosynthesis of a novel semiconductor polymer based on alkyl vinylthiophene derivative in the presence of an ionic liquid (IL). The polymerization was performed under galvanostatic conditions and the polymer was studied as potential donor component of a multilayer heterojunction organic solar cell (OSC). The monomer used was (E)-1,2-di-(3-octyl-2-thienyl) vinylene (OTV) and the IL used for the electropolymerization was 1-octyl-3-methylimidazole hexafluorophosphate C8mimPF6. Optical properties, stability and morphology of the polymer were analyzed using FT-IR, UV-vis, Raman and XPS spectroscopy. Voltammetry analysis and scanning electron microscopy (SEM-EDX) were also performed on the polymer. The OSC assembled with the polymer of OTV was used as electro donor and C60 as acceptor. Molybdenum trioxide (MoO3) and bathocuproine (BCP) were used as buffer layer between anode and cathode respectively. I-V curves, in the dark and under AM 1.5 solar simulator were performed to measure its efficiency.
