RESUMO
A new bifunctionalized TiO(2) film containing a dye-sensitized region and a degradation region was described. A similar structure of dye-sensitized solar cell (DSSC) was fabricated in the dye-sensitized region to accomplish separation of electrons from positive charges, and separation of dye from pollutants to avoid dye decomposition. The bifunctionalized TiO(2) film electrode and anode electrode can degrade methyl orange (MO) in reactors A and B, respectively. The degradation efficiency was enhanced remarkably by an external electrical potential. The decolorization of MO reaches as high as 95% after 2 h visible light irradiation at an external potential of 0.5 V along with a loss of 41% total organic carbon (TOC). The possible reason for the improvement of degradation by external DC potential was discussed. Effects of pH and inorganic salts on the decolorization are present.
Assuntos
Compostos Azo/química , Corantes/química , Titânio/química , Poluentes Químicos da Água/química , Compostos Azo/efeitos da radiação , Cor , Corantes/efeitos da radiação , Eletrodos , Concentração de Íons de Hidrogênio , Luz , Nitratos/química , Fotólise , Cloreto de Sódio/química , Sulfatos/química , Poluentes Químicos da Água/efeitos da radiação , Purificação da Água/métodosRESUMO
Three triphenylamine derivatives containing ferrocenyl groups (JW6, JW7 and JW8) were synthesized by facile syntheses. Their HOMO levels match the valence band energy of CH3NH3PbI3. The introduction of ferrocenyl was aimed to obtain hole transporting materials with high mobility for perovskite solar cells. JW7 shows higher hole mobility (4.2 × 10-4 cm2 V-1 s-1) than JW6 (1.3 × 10-4 cm2 V-1 s-1) and JW8 (1.5 × 10-4 cm2 V-1 s-1). Their film-forming properties are affected by their molecule structures. The methoxyl and N,N-dimethyl terminal substituents of JW7 and JW8 are beneficial for having better solubility than JW6. The regular mesoporous TiO2-based perovskite solar cells (n-i-p) and the inverted planar heterojunction perovskite solar cells (p-i-n) fabricated using JW7 show the highest power conversion efficiency of 9.36% and 11.43% under 100 mW cm-2 AM1.5G solar illumination. For p-i-n cells, the standard HTM PEDOT-based cell reaches an efficiency of 12.86% under the same conditions.
RESUMO
A degradation device containing a bifunctionalized TiO(2) film electrode and an anode electrode was described. The bifunctionalized TiO(2) film electrode is composite of an area of dye-sensitized TiO(2) film, electrolyte and counter electrode, which is similar to the structure of dye-sensitized solar cells (DSSCs). Electrons and positive charges induced by visible light absorption of dyes could arrive at the degradation region of the bifunctionalized TiO(2) film electrode and the anode electrode, respectively. Both could produce hydroxyl radicals (OH) to participate in the degradation reaction. The degradation efficiency was enhanced remarkably by an external potential. Meanwhile, the effects of dye-sensitized TiO(2) film area and pH value on the degradation of 4-chlorophenol (4-CP) were tested. An insight into degradation pathway, plausible mechanism for 4-CP and degradation of other phenols were also discussed here.
Assuntos
Corantes/química , Eletroquímica/métodos , Fenóis/química , Fotoquímica/métodos , Titânio/química , Catálise , Concentração de Íons de Hidrogênio , Radical Hidroxila/químicaRESUMO
A new strategy to photocatalytic degradation of 4-cholophenol (4-CP) under visible light irradiation was described. The TiO(2) film deposited on an ordinary glass sheet was distributed into two zones. One zone was sensitized by N719 dye and fabricated to be a sandwich type cell with a similar structure of dye-sensitized solar cells. The other zone was inserted into pollutants solution for degradation. A highly oxidized overvoltage anode was achieved from the dye-sensitized zone. The bifunctionalized TiO(2) film and the anode could degrade 4-chlorophenol in two separate reactors with 97% and 96% removal of 4-CP after 5h, respectively. The degradation efficiency could be improved by addition of FeSO(4). The as-prepared bifunctionalized TiO(2) film was comparably stable in the process of degradation.
Assuntos
Clorofenóis/química , Fotoquímica , Titânio/química , CatáliseRESUMO
PPh3-catalyzed alpha-addition reactions of 1-(o-hydroxyaryl)-1,3-diketones to terminal alkynoates involving carbon-carbon bond cleavage to give multifunctional vinylesters are described.