This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glas...This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glass(FTO)and photoactive thin films such as hematite for low‐cost water oxidation reaction.High‐resolution electron microscopy(SEM,TEM,STEM),atomic force microscopy(AFM),elemental chemical mapping(EELS,EDS)and photoelectrochemical(PEC)investigations reveal that the mechanical stress,lattice mismatch,electron energy barrier,and voids between FTO and hematite at the back‐contact interface as well as short‐circuit and detrimental reaction between FTO and the electrolyte can be alleviated by engineering the chemical composition of the precursor solutions,thus increasing the overall efficiency of these low‐cost photoanodes for water oxidation reaction for a clean and sustainable generation of hydrogen from PEC water‐splitting.These findings are of significant importance to improve the charge collection efficiency by minimizing electron‐hole recombination observed at back‐contact interfaces and grain boundaries in mesoporous electrodes,thus improving the overall efficiency and scalability of low‐cost PEC water splitting devices.展开更多
Catalytic converting CO2 into fuels with the help of solar energy is regarded as‘dream reaction’,as both energy crisis and environmental issue can be mitigated simultaneously.However,it is still suffering from low e...Catalytic converting CO2 into fuels with the help of solar energy is regarded as‘dream reaction’,as both energy crisis and environmental issue can be mitigated simultaneously.However,it is still suffering from low efficiency due to narrow solar-spectrum utilization and sluggish heterogeneous reaction kinetics.In this work,we demonstrate that catalytic reduction of CO2 can be achieved over Au nanoparticles(NPs)deposited rutile under full solar-spectrum irradiation,boosted by solar-heating effect.We found that UV and visible light can initiate the reaction,and the heat from IR light and local surface-plasmon resonance relaxation of Au NPs can boost the reaction kinetically.The apparent activation energy is determined experimentally and is used to explain the superior catalytic activity of Au/rutile to rutile in a kinetic way.We also find the photo-thermal synergy in the Au/rutile system.We envision that this work may facilitate understanding the kinetics of CO2 reduction and developing feasible catalytic systems with full solar spectrum utilization for practical artificial photosynthesis.展开更多
A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1Hbenzimidazole]was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy,elemental anal...A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1Hbenzimidazole]was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy,elemental analysis,electrospray ionization high‐resolution mass spectrometry,and thermogravimetric analysis.The molecular structure was confirmed by single‐crystal X‐ray diffraction.Complex1consists of mononuclear tetrahedral zinc(II)units with a locked geometry resulting from weak intramolecular S···?and?–?interligand interactions.The benzimidazole ligand and its zinc(II)complex were readily obtained through a simple synthetic route.The catalytic activity of1was investigated in the coupling of carbon dioxide with epoxides to produce cyclic carbonates,and a series of parameters were evaluated.The complex efficiently catalyzed the transformation of various epoxides under solvent‐free conditions,with good conversions,turnover numbers,and turnover frequencies.展开更多
In this paper, we wish to respond to the call for expansion on our knowledge about teacher beliefs(Kubanyiova & Feryok, 2015) and discuss findings of studies on teacher emotions conducted in Brazil with both in-se...In this paper, we wish to respond to the call for expansion on our knowledge about teacher beliefs(Kubanyiova & Feryok, 2015) and discuss findings of studies on teacher emotions conducted in Brazil with both in-service and pre-service teachers of English. More specifically, we focus 1) on the kinds of emotions these teachers have reported feeling, and 2) on the relationship between beliefs and emotions. The results have shown: 1) the diversity of emotions teachers experience in their teacher education;and 2) how these emotions interact in dynamic and complex ways with their beliefs about teaching English in Brazil. The findings suggest that looking into the interrelationships between emotions and beliefs can shed light onto our understanding of the teachers’ thinking and practices in their contexts. Implications and questions for further research will be discussed in light of the studies reviewed.展开更多
基金supported by CNPq,CAPES,FAPESP(2017/02317-2),FAPESP(2017/11986-5)Shell and the strategic importance of the support given by ANP(Brazil’s National Oil,Natural Gas and Biofuels Agency)through the R&D levy regulation+2 种基金PRH49/UFABC-ANP for the fellowshipthe National Natural Science Foundation of China(NSFC)the Outstanding Talent Program of Shaanxi Province as well as FAPESP(2017/11986-5)
文摘This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glass(FTO)and photoactive thin films such as hematite for low‐cost water oxidation reaction.High‐resolution electron microscopy(SEM,TEM,STEM),atomic force microscopy(AFM),elemental chemical mapping(EELS,EDS)and photoelectrochemical(PEC)investigations reveal that the mechanical stress,lattice mismatch,electron energy barrier,and voids between FTO and hematite at the back‐contact interface as well as short‐circuit and detrimental reaction between FTO and the electrolyte can be alleviated by engineering the chemical composition of the precursor solutions,thus increasing the overall efficiency of these low‐cost photoanodes for water oxidation reaction for a clean and sustainable generation of hydrogen from PEC water‐splitting.These findings are of significant importance to improve the charge collection efficiency by minimizing electron‐hole recombination observed at back‐contact interfaces and grain boundaries in mesoporous electrodes,thus improving the overall efficiency and scalability of low‐cost PEC water splitting devices.
基金supported by the Belt and Road Initiative by Chinese Academy of Sciencesthe National Natural Science Foundation of China(21673052,11404074)
文摘Catalytic converting CO2 into fuels with the help of solar energy is regarded as‘dream reaction’,as both energy crisis and environmental issue can be mitigated simultaneously.However,it is still suffering from low efficiency due to narrow solar-spectrum utilization and sluggish heterogeneous reaction kinetics.In this work,we demonstrate that catalytic reduction of CO2 can be achieved over Au nanoparticles(NPs)deposited rutile under full solar-spectrum irradiation,boosted by solar-heating effect.We found that UV and visible light can initiate the reaction,and the heat from IR light and local surface-plasmon resonance relaxation of Au NPs can boost the reaction kinetically.The apparent activation energy is determined experimentally and is used to explain the superior catalytic activity of Au/rutile to rutile in a kinetic way.We also find the photo-thermal synergy in the Au/rutile system.We envision that this work may facilitate understanding the kinetics of CO2 reduction and developing feasible catalytic systems with full solar spectrum utilization for practical artificial photosynthesis.
文摘A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1Hbenzimidazole]was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy,elemental analysis,electrospray ionization high‐resolution mass spectrometry,and thermogravimetric analysis.The molecular structure was confirmed by single‐crystal X‐ray diffraction.Complex1consists of mononuclear tetrahedral zinc(II)units with a locked geometry resulting from weak intramolecular S···?and?–?interligand interactions.The benzimidazole ligand and its zinc(II)complex were readily obtained through a simple synthetic route.The catalytic activity of1was investigated in the coupling of carbon dioxide with epoxides to produce cyclic carbonates,and a series of parameters were evaluated.The complex efficiently catalyzed the transformation of various epoxides under solvent‐free conditions,with good conversions,turnover numbers,and turnover frequencies.
文摘In this paper, we wish to respond to the call for expansion on our knowledge about teacher beliefs(Kubanyiova & Feryok, 2015) and discuss findings of studies on teacher emotions conducted in Brazil with both in-service and pre-service teachers of English. More specifically, we focus 1) on the kinds of emotions these teachers have reported feeling, and 2) on the relationship between beliefs and emotions. The results have shown: 1) the diversity of emotions teachers experience in their teacher education;and 2) how these emotions interact in dynamic and complex ways with their beliefs about teaching English in Brazil. The findings suggest that looking into the interrelationships between emotions and beliefs can shed light onto our understanding of the teachers’ thinking and practices in their contexts. Implications and questions for further research will be discussed in light of the studies reviewed.