A molecular cobaloxime cocatalyst and ultrathin FeOOH nanolayers co-modifiedBiVO_(4) photoanode for efficient photoelectrochemical water oxidation

BiVO_(4) has been attracting a lot of interest in photoelectrochemical (PEC) water oxidation due to its efficient solar absorption and appropriate band positions.So far,sluggish water oxidation kinetics and fast photogenerated charge recombination still hinder the PEC performance ofBiVO_(4) .In this study,a novel PEC photoanode was designed by depositing ultrathin FeOOH nanolayers on the surface of nanoporousBiVO_(4) electrode,followed by modification with a cobaloxime (Co(dmgH)_(2)(4-COOH-py)Cl) molecular cocatalyst.Under irradiation of a 100 mW cm^(-2)(AM 1.5G) Xe lamp,the photocurrent density of the cobaloxime/FeOOH/BiVO_(4) composite photoanode reached 5.1 mA cm^(-2)at 1.23 V vs.RHE in 1.0 M potassium borate buffer solution (pH=9.0).The onset potential of the optimal cobaloxime/FeOOH/BiVO_(4) photoanode exhibited a 460 m V cathodic shift relative to bareBiVO_(4) .In addition,the surface charge injection efficiency of the composite photoanode reached~80%at 1.23 V vs.RHE and the incident photon-to-current efficiency (IPCE) reached~88%at 420 nm.

Removal of high concentrations of polycyclic aromatic hydrocarbons from contaminated soil by biodiesel

Solubilizing experiments were carried out to evaluate the ability of biodiesel to remove polycyclic aromatic hydrocarbons(PAHs)from highly contaminated manufactured gas plant(MGP)and PAHs spiked soils with hydroxypropyl-β-cyclodextrin(HPCD)and tween 80 as comparisons.Biodiesel displayed the highest solubilities of phenanthrene(420.7 mg·L^(-1)),pyrene(541.0 mg·L^(-1)),and benzo(a)pyrene(436.3 mg·L^(-1)).These corresponded to several fold increases relative to 10%HPCD and tween 80.Biodiesel showed a good efficiency for PAH removal from the spiked and MGP soils for both low molecular weight and high molecular weight PAHs at high concentrations.Biodiesel was the best agent for PAH removal from the spiked soils as compared with HPCD and tween 80;as over 77.9%of individual PAH were removed by biodiesel.Tween 80 also showed comparable capability with biodiesel for PAH solubilization at a concentration of 10%for the spiked soils.Biodiesel solubilized a wider range of PAHs as compared to HPCD and tween 80 for the MPG soils.At PAH concentrations of 229.6 and 996.9 mg·kg^(-1),biodiesel showed obvious advantage over the 10%HPCD and tween 80,because it removed higher than 80%of total PAH.In this study,a significant difference between PAH removals from the spiked and field MGP soils was observed;PAH removals from the MGP soil by HPCD and tween 80 were much lower than those from the spiked soil.These results demonstrate that the potential for utilizing biodiesel for remediation of highly PAH-contaminated soil has been established.