We investigated the photovoltaic properties of series of TiO 2 photocatalysts by means of SPS and found that the thresholds of TiO 2 particles blue shift with their particle sizes decreasing and crystal phases changin...We investigated the photovoltaic properties of series of TiO 2 photocatalysts by means of SPS and found that the thresholds of TiO 2 particles blue shift with their particle sizes decreasing and crystal phases changing from rutile TiO 2 to anatase TiO 2. Combining with the photodegradation activities of TiO 2 on C 7H 16 , it was concluded that the photocatalytic activities of TiO 2 increase with their thresholds increasing,which can be explained using energy band theory. We also investigated the relationship beween the photovoltaic properties and photocatalytic activities of B TiO 2 before and after photooxidation on C 7H 16 , SO 2 and C 7H 16 +SO 2, respectively and found adsorbates at the surface of TiO 2 affect their photocatalytic activities and conduction types of surface layer.展开更多
The surface photovoltaic properties of four azo pigments(A, B, C, D) were studied by surface photovoltage spectra (SPS) and field induced surface photovoltage spectra (FISPS). The SPV responses of samples A and D were...The surface photovoltaic properties of four azo pigments(A, B, C, D) were studied by surface photovoltage spectra (SPS) and field induced surface photovoltage spectra (FISPS). The SPV responses of samples A and D were all enhanced when a negative electric field was applied and were all weaken when a positive voltage was applied. It shows that samples A and D indicate n type characteristics. On the contrary, samples B and C indicate p type characteristics. Combining with phase technique and molecular structure of azo pigments, the effect of group on Fermi energy level and conduction type of azo pigments was discussed.展开更多
The photovoltaic properties of dimeric porphyrin have been studied by means of surface photovoltage spectrum(SPS) and field induced surface photovoltage spectrum(FISPS). The results show that a negative SPV response b...The photovoltaic properties of dimeric porphyrin have been studied by means of surface photovoltage spectrum(SPS) and field induced surface photovoltage spectrum(FISPS). The results show that a negative SPV response band(P) appears in the long wave region which takes on n type character and the π π * transition band takes on p type character. P band disappears under high vacuum and appears under O 2 atmosphere. The photo charge transfer process generated between π π * transition band of dimeric porphyrin and P band, which has been attributed to the photo adsorption and photo desorption of O 2 on the surface of dimeric porphyrin.展开更多
文摘We investigated the photovoltaic properties of series of TiO 2 photocatalysts by means of SPS and found that the thresholds of TiO 2 particles blue shift with their particle sizes decreasing and crystal phases changing from rutile TiO 2 to anatase TiO 2. Combining with the photodegradation activities of TiO 2 on C 7H 16 , it was concluded that the photocatalytic activities of TiO 2 increase with their thresholds increasing,which can be explained using energy band theory. We also investigated the relationship beween the photovoltaic properties and photocatalytic activities of B TiO 2 before and after photooxidation on C 7H 16 , SO 2 and C 7H 16 +SO 2, respectively and found adsorbates at the surface of TiO 2 affect their photocatalytic activities and conduction types of surface layer.
文摘The surface photovoltaic properties of four azo pigments(A, B, C, D) were studied by surface photovoltage spectra (SPS) and field induced surface photovoltage spectra (FISPS). The SPV responses of samples A and D were all enhanced when a negative electric field was applied and were all weaken when a positive voltage was applied. It shows that samples A and D indicate n type characteristics. On the contrary, samples B and C indicate p type characteristics. Combining with phase technique and molecular structure of azo pigments, the effect of group on Fermi energy level and conduction type of azo pigments was discussed.
文摘The photovoltaic properties of dimeric porphyrin have been studied by means of surface photovoltage spectrum(SPS) and field induced surface photovoltage spectrum(FISPS). The results show that a negative SPV response band(P) appears in the long wave region which takes on n type character and the π π * transition band takes on p type character. P band disappears under high vacuum and appears under O 2 atmosphere. The photo charge transfer process generated between π π * transition band of dimeric porphyrin and P band, which has been attributed to the photo adsorption and photo desorption of O 2 on the surface of dimeric porphyrin.