We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus re...We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus resulting in a high efficient charge transportation and low electron–hole recombination in the TiO_2–BiVO_4. Therefore, the BiVO_4/TiO_2(N_2) NTs photoanode enabled with a significantly enhanced photocurrent of 2.73 mA cm^(-2)(at 1 V vs. Ag/Ag Cl) and a degradation efficiency in the oxidation of dyes under visible light. Field emission scanning electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectrometer, and UV–Vis absorption spectrum were conducted to characterize the photoanode and demonstrated the presence of both metal oxides as a junction composite.展开更多
Copper and titanium remain relatively plentiful in earth crust.Therefore,using them in solar energy conversion technologies are of significant interest.In this work,cuprous oxide（Cu2O）-modified short TiO2 nanotube a...Copper and titanium remain relatively plentiful in earth crust.Therefore,using them in solar energy conversion technologies are of significant interest.In this work,cuprous oxide（Cu2O）-modified short TiO2 nanotube array electrode was prepared based on the following two design ideas:first,the short titania nanotubes obtained from sonoelectrochemical anodization possess excellent charge separation and transportation properties as well as desirable mechanical stability;second,the sonoelectrochemical deposition technique favours the improvement in the combination between Cu2O and TiO2 nanotubes,and favours the dispersion of Cu2O particles.UV-Vis absorption and photo-electronchemical measurements proved that the Cu2O coating extended the visible spectrum absorption and the solar spectrum-induced photocurrent response.Under AM1.5 irradiation,the photocurrent density of the composite electrode（i.e.sonoelectrochemical deposition for 5 min） was more than 4.75 times as high as the pure nanotube electrode.Comparing the photoactivity of the Cu2O/TiO2 electrode obtained using sonoelectrochemical deposition with others that synthesized using plain electrochemical deposition,the photocurrent density of the former electrode was 2.2 times higher than that of the latter when biased at 1.0 V（vs.Ag/AgCl）.The reproducible photocurrent response under intermittent illumination demonstrated the excellent stability of the composite electrode.Such kind of composite electrode material will have many potential applications in solar cell and other fields.展开更多
TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solution...TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solutions in the absence of any other additives. The structure and optical properties of Cu2O-loaded TiO2 nanotube arrays （Cu2O-TNTs） were analyzed by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and UV-Vis absorption, and the photoelectrochemical performance was measured using an electrochemical work station with a three-electrode configuration. The results show that the Cu2O particles distribute uniformly on the highly ordered anatase TiO2 nanotube arrays. The morphologies of Cu2O crystals change from branched, truncated octahedrons to dispersive single octahedrons with increasing deposition current densities. The Cu2O- TNTs exhibited remarkable visible light responses with obvious visible light absorption and greatly enhanced visible light photoelectrochemical performance. The I-V characteristics under visible light irradiation show a distinct plateau in the region between approximately -0.3 and 0 V, resulting in higher open-circuit voltages and larger short-circuit currents with increased Cu2O deposition.展开更多
The Cu2O/TiO2 p-n heterojunction composite photoelectrodes were prepared by depositing Cu 2 O nanoparticles on the surface of TiO 2 nanotubes via anodic oxidation and constant current deposition.Field emission scannin...The Cu2O/TiO2 p-n heterojunction composite photoelectrodes were prepared by depositing Cu 2 O nanoparticles on the surface of TiO 2 nanotubes via anodic oxidation and constant current deposition.Field emission scanning electron microscopy(SEM)and high-resolution transmission electron microscopy(HRTEM)analyses showed that Cu 2 O nanoparticles not only deposited on the surface of TiO 2 nanotube array,but also on the wall of TiO 2 nanotubes.The Cu 2 O deposition amount could be adjusted by changing the deposition time.The photoelectrochemical cathodic protection(PECCP)performance of the prepared photoelectrodes for 316L stainless steel(SS)was tested under visible light.The constant current deposition time had a signifi cant eff ect on the PECCP performance of Cu 2 O/TiO 2-X photoelectrodes and Cu 2 O/TiO 2-20 had the best PECCP performance for the coupled 316L SS.This was attributed to the appropriate amount and thickness of Cu 2 O to form p-n heterojunctions with TiO 2,in which separation of the photogenerated carriers was accelerated and transfer of the photogenerated electrons to 316L SS for PECCP was facilitated.展开更多
The application of TiO2-based devices is mainly dependent on their crystalline structure, morphology, size, and exposed facets. Two kinds of TiO2 with different structures, namely TiO2 pompons and TiO2 nanotubes, have...The application of TiO2-based devices is mainly dependent on their crystalline structure, morphology, size, and exposed facets. Two kinds of TiO2 with different structures, namely TiO2 pompons and TiO2 nanotubes, have been prepared by the hydrothermal method. TiO2 with different structures is characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and Brunauer Emmett-Teller （BET） surface area analysis. Solar cells based on poly（3-hexylthiophene） （P3HT） and TiO2 with different structures are fabricated. In the device ITO/TiO2/P3HT/Au, the P3HT is designed to act as the electron donor, and TiO2 pompons and TiO2 nanotubes act as the electron acceptor. The effects of the TiO2 structure on the performance of hybrid heterojunction solar cells are investigated. The device with TiO2 pompons has an open circuit voltage （Voc） of 0.51 V, a short circuit current （Jsc） of 0.21 mA/cm2, and a fill factor （FF） of 28.3%. Another device with TiO2 nanotubes has a Voc of 0.5 V, Jsc of 0.27 mA/cm2, and FF of 28.4%. The results indicate that the TiO2 nanotubes with a unidimensional structure have better carrier transport and light absorption properties than TiO2 pompons. Consequently, the solar cell based on TiO2 nanotubes has a better performance.展开更多
基金the National Nature Science Foundation of China(21507085,21576162)Shanghai Sailing Program of China(14YF1401500)for financial support
文摘We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus resulting in a high efficient charge transportation and low electron–hole recombination in the TiO_2–BiVO_4. Therefore, the BiVO_4/TiO_2(N_2) NTs photoanode enabled with a significantly enhanced photocurrent of 2.73 mA cm^(-2)(at 1 V vs. Ag/Ag Cl) and a degradation efficiency in the oxidation of dyes under visible light. Field emission scanning electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectrometer, and UV–Vis absorption spectrum were conducted to characterize the photoanode and demonstrated the presence of both metal oxides as a junction composite.
基金the State Key Development Program for Basic Research of China (Grant No.2009CB220004)the Shanghai Basic Research Key Project (08JC1411300,0952nm01800)+1 种基金the National High Technology Research and Development Program of China (Grant No.2009 AA063003)Shanghai Tongji Gao Tingyao Environmental Science and Technology Development Foundation for financial support
文摘Copper and titanium remain relatively plentiful in earth crust.Therefore,using them in solar energy conversion technologies are of significant interest.In this work,cuprous oxide（Cu2O）-modified short TiO2 nanotube array electrode was prepared based on the following two design ideas:first,the short titania nanotubes obtained from sonoelectrochemical anodization possess excellent charge separation and transportation properties as well as desirable mechanical stability;second,the sonoelectrochemical deposition technique favours the improvement in the combination between Cu2O and TiO2 nanotubes,and favours the dispersion of Cu2O particles.UV-Vis absorption and photo-electronchemical measurements proved that the Cu2O coating extended the visible spectrum absorption and the solar spectrum-induced photocurrent response.Under AM1.5 irradiation,the photocurrent density of the composite electrode（i.e.sonoelectrochemical deposition for 5 min） was more than 4.75 times as high as the pure nanotube electrode.Comparing the photoactivity of the Cu2O/TiO2 electrode obtained using sonoelectrochemical deposition with others that synthesized using plain electrochemical deposition,the photocurrent density of the former electrode was 2.2 times higher than that of the latter when biased at 1.0 V（vs.Ag/AgCl）.The reproducible photocurrent response under intermittent illumination demonstrated the excellent stability of the composite electrode.Such kind of composite electrode material will have many potential applications in solar cell and other fields.
基金Funded by the National Natural Science Foundation of China(No.51175363)the Youth Staff Fund of Taiyuan University of Technology(Nos.K201016,K201013)+1 种基金the Specialized Fund for Innovative of College Students of Taiyuan City(No.09122018)the Program for Changjiang Scholar and Innovative Research Team in University(No.IRT0972)
文摘TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solutions in the absence of any other additives. The structure and optical properties of Cu2O-loaded TiO2 nanotube arrays （Cu2O-TNTs） were analyzed by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and UV-Vis absorption, and the photoelectrochemical performance was measured using an electrochemical work station with a three-electrode configuration. The results show that the Cu2O particles distribute uniformly on the highly ordered anatase TiO2 nanotube arrays. The morphologies of Cu2O crystals change from branched, truncated octahedrons to dispersive single octahedrons with increasing deposition current densities. The Cu2O- TNTs exhibited remarkable visible light responses with obvious visible light absorption and greatly enhanced visible light photoelectrochemical performance. The I-V characteristics under visible light irradiation show a distinct plateau in the region between approximately -0.3 and 0 V, resulting in higher open-circuit voltages and larger short-circuit currents with increased Cu2O deposition.
基金Supported by the National Natural Science Foundation of China(Nos.41576114,41676069)the State Key Laboratory for Marine Corrosion and Protection,Luoyang Ship Material Research Institute,China(No.614290101011703)the Qingdao Innovative Leading Talent Foundation(No.15-10-3-15-(39)-zch)。
文摘The Cu2O/TiO2 p-n heterojunction composite photoelectrodes were prepared by depositing Cu 2 O nanoparticles on the surface of TiO 2 nanotubes via anodic oxidation and constant current deposition.Field emission scanning electron microscopy(SEM)and high-resolution transmission electron microscopy(HRTEM)analyses showed that Cu 2 O nanoparticles not only deposited on the surface of TiO 2 nanotube array,but also on the wall of TiO 2 nanotubes.The Cu 2 O deposition amount could be adjusted by changing the deposition time.The photoelectrochemical cathodic protection(PECCP)performance of the prepared photoelectrodes for 316L stainless steel(SS)was tested under visible light.The constant current deposition time had a signifi cant eff ect on the PECCP performance of Cu 2 O/TiO 2-X photoelectrodes and Cu 2 O/TiO 2-20 had the best PECCP performance for the coupled 316L SS.This was attributed to the appropriate amount and thickness of Cu 2 O to form p-n heterojunctions with TiO 2,in which separation of the photogenerated carriers was accelerated and transfer of the photogenerated electrons to 316L SS for PECCP was facilitated.
基金Project supported by the Ministry of Science and Technology of China (Grant No. 2011CB932802)the National Natural Science Foundation of China (Grant No. 60978060)the Beijing Municipal Science & Technology Commission,China (Grant No. Z090803044009001)
文摘The application of TiO2-based devices is mainly dependent on their crystalline structure, morphology, size, and exposed facets. Two kinds of TiO2 with different structures, namely TiO2 pompons and TiO2 nanotubes, have been prepared by the hydrothermal method. TiO2 with different structures is characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and Brunauer Emmett-Teller （BET） surface area analysis. Solar cells based on poly（3-hexylthiophene） （P3HT） and TiO2 with different structures are fabricated. In the device ITO/TiO2/P3HT/Au, the P3HT is designed to act as the electron donor, and TiO2 pompons and TiO2 nanotubes act as the electron acceptor. The effects of the TiO2 structure on the performance of hybrid heterojunction solar cells are investigated. The device with TiO2 pompons has an open circuit voltage （Voc） of 0.51 V, a short circuit current （Jsc） of 0.21 mA/cm2, and a fill factor （FF） of 28.3%. Another device with TiO2 nanotubes has a Voc of 0.5 V, Jsc of 0.27 mA/cm2, and FF of 28.4%. The results indicate that the TiO2 nanotubes with a unidimensional structure have better carrier transport and light absorption properties than TiO2 pompons. Consequently, the solar cell based on TiO2 nanotubes has a better performance.
