Formic acid （HCOOH） decomposition at Pt film electrode has been studied by electrochem- ical in situ FTIR spectroscopy under attenuated-total-reflection configuration, in order to clarify whether bridge-bonded forma...Formic acid （HCOOH） decomposition at Pt film electrode has been studied by electrochem- ical in situ FTIR spectroscopy under attenuated-total-reflection configuration, in order to clarify whether bridge-bonded formate （HCOOD） is the reactive intermediate for COad for-mation from HCOOH molecules. When switching from HCOOH-free solution to HCOOH- containing solution at constant potential （E=0.4 V vs. RHE）, we found that immediately upon solution switch COad formation rate is the highest, while surface coverage of formate is zero, then after COad formation rate decreases, while formate coverage reaches a steady state coverage quickly within ca. 1 s. Potential step experiment from E=0.75 V to 0.35 V, reveals that formate band intensity drops immediately right after the potential step, while the COad signal develops slowly with time. Both facts indicate that formate is not the reactive intermediate for formic acid dehydration to CO.展开更多
A series of carbonaceous mesophase spherule/activated carbon composites were prepared as anode materials for super lithium ion capacitors using carbonaceous mesophase spherules as the core materials and pitch as the a...A series of carbonaceous mesophase spherule/activated carbon composites were prepared as anode materials for super lithium ion capacitors using carbonaceous mesophase spherules as the core materials and pitch as the active carbon shell precursor.The structures of the composites were examined by scanning electron microscopy and X-ray diffractometry.The electrochemical performance was investigated in electric double layer capacitor and half-cell.The results show that,the composite exhibits good performance in both capacitor and battery with a high reversible capacity of 306.6 mA·h/g(0.2C) in the half-cell,along with a capacitance of 25.8 F/g in the capacitor when an optimum ratio of carbonaceous mesophase spherules to active carbon is adopted.The composite also shows a favorable rate performance and good cycle ability.A working model of this anode in super lithium ion capacitors was established.展开更多
Three alcohol/water-soluble porphyrins, Zn-TPyPMeI： zinc（II） meso-tetra（N-methyl-4-pyridyl） porphyrin tetra-iodide, Zn- TPyPAdBr： zinc（II） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-b...Three alcohol/water-soluble porphyrins, Zn-TPyPMeI： zinc（II） meso-tetra（N-methyl-4-pyridyl） porphyrin tetra-iodide, Zn- TPyPAdBr： zinc（II） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide and MnC1-TPyPAdBr： man- ganese（III） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide were employed as cathode interlayers to fabricate polymer solar cells （PSCs）. The PCvaBM （[6,6]-phenyl C71 butyric acid methyl ester） and PCDTBT （poly[N-9＂- hepta-decanyl-2,7-carbazole-alt-5,5-（4＇,7＇-di-2-thienyl-2＇,3＇-benzothiadiazole）]）-blend films were used as active layers in polymer solar cells （PSCs）. The PSCs with alcohol/water-soluble porphyrins interlayer showed obviously higher power con- version efficiency （PCE） than those without interlayers. The highest PCE, 6.86%, was achieved for the device with MnCl- TPyPAdBr as an interlayer. Ultraviolet photoemission spectroscopic （UPS）, carrier mobility, atomic force microscopy （AFM） and contact angle （0） characterizations demonstrated that the porphyrin molecules can result in the formation of interfacial dipole layer between active layer and cathode. The interfacial dipole layer can obviously improve the open-circuit voltage （Voc） and charge extraction, and sequentially lead to the increase of PCE.展开更多
文摘Formic acid （HCOOH） decomposition at Pt film electrode has been studied by electrochem- ical in situ FTIR spectroscopy under attenuated-total-reflection configuration, in order to clarify whether bridge-bonded formate （HCOOD） is the reactive intermediate for COad for-mation from HCOOH molecules. When switching from HCOOH-free solution to HCOOH- containing solution at constant potential （E=0.4 V vs. RHE）, we found that immediately upon solution switch COad formation rate is the highest, while surface coverage of formate is zero, then after COad formation rate decreases, while formate coverage reaches a steady state coverage quickly within ca. 1 s. Potential step experiment from E=0.75 V to 0.35 V, reveals that formate band intensity drops immediately right after the potential step, while the COad signal develops slowly with time. Both facts indicate that formate is not the reactive intermediate for formic acid dehydration to CO.
基金Project(2007BAE12B00) supported by the National Key Technology R&D Program of ChinaProject(50974136) supported by the National Natural Science Foundation of China
文摘A series of carbonaceous mesophase spherule/activated carbon composites were prepared as anode materials for super lithium ion capacitors using carbonaceous mesophase spherules as the core materials and pitch as the active carbon shell precursor.The structures of the composites were examined by scanning electron microscopy and X-ray diffractometry.The electrochemical performance was investigated in electric double layer capacitor and half-cell.The results show that,the composite exhibits good performance in both capacitor and battery with a high reversible capacity of 306.6 mA·h/g(0.2C) in the half-cell,along with a capacitance of 25.8 F/g in the capacitor when an optimum ratio of carbonaceous mesophase spherules to active carbon is adopted.The composite also shows a favorable rate performance and good cycle ability.A working model of this anode in super lithium ion capacitors was established.
基金supported by the National Basic Research Program of China(2014CB643500)the National Natural Science Foundation of China(51273077,51173065)
文摘Three alcohol/water-soluble porphyrins, Zn-TPyPMeI： zinc（II） meso-tetra（N-methyl-4-pyridyl） porphyrin tetra-iodide, Zn- TPyPAdBr： zinc（II） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide and MnC1-TPyPAdBr： man- ganese（III） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide were employed as cathode interlayers to fabricate polymer solar cells （PSCs）. The PCvaBM （[6,6]-phenyl C71 butyric acid methyl ester） and PCDTBT （poly[N-9＂- hepta-decanyl-2,7-carbazole-alt-5,5-（4＇,7＇-di-2-thienyl-2＇,3＇-benzothiadiazole）]）-blend films were used as active layers in polymer solar cells （PSCs）. The PSCs with alcohol/water-soluble porphyrins interlayer showed obviously higher power con- version efficiency （PCE） than those without interlayers. The highest PCE, 6.86%, was achieved for the device with MnCl- TPyPAdBr as an interlayer. Ultraviolet photoemission spectroscopic （UPS）, carrier mobility, atomic force microscopy （AFM） and contact angle （0） characterizations demonstrated that the porphyrin molecules can result in the formation of interfacial dipole layer between active layer and cathode. The interfacial dipole layer can obviously improve the open-circuit voltage （Voc） and charge extraction, and sequentially lead to the increase of PCE.
