Luminescent solar concentrators (LSCs) with styrene (ST) and methylmethacrylate (MMA) of different percentage as the matrix were prepared by a casting method using ponceau 2R. DSC has been used to compare the thermal ...Luminescent solar concentrators (LSCs) with styrene (ST) and methylmethacrylate (MMA) of different percentage as the matrix were prepared by a casting method using ponceau 2R. DSC has been used to compare the thermal stability of the different LSCs. FTIR spectroscopy shows that appearance of -N=N- for ponceau 2R in all ST/MMA matrixes indicating that the highest stability of this kind of dye in these matrixes. The values of the optical band gap (Eg) have been obtained from direct allowed transition before and after the samples have been exposed to sunlight for 9 weeks. Photodegradation studies revealed that the more photostable dye doped in PMMA matrix than in other matrixes. The results showed that the homo PMMA/ponceau 2R system has the highest fluorescence quantum yield (Qf). Therefore this sample can be selected for field performance of fluorescent solar collectors. The photovoltaic cell coupled with homo PMMA/2R LSC shows a maximum efficiency, 2% compared to the normal one.展开更多
The mechanism of oxidation and degradation effect of phytate-modified biochar catalyzed persulfate on Ponceau 2R was investigated.Chemical-structural properties of phytate-modified biochar,such as surface morphology a...The mechanism of oxidation and degradation effect of phytate-modified biochar catalyzed persulfate on Ponceau 2R was investigated.Chemical-structural properties of phytate-modified biochar,such as surface morphology and surface oxygen-containing functional groups were characterized.The results suggest that modified biochar has better oxidation performance than unmodified biochar,and the modified biochar generated at 500℃pyrolysis temperature can catalyze peroxymonosulfate(PMS)system with high efficiency,in large pH and temperature scope.And the degradation mechanism of Ponceau 2R by biochar-catalyzed PMS generation(BC-PMS)system was researched.It revealed that PBC300(phytate-modified biochar pyrolyzed at 300℃),PBC500(phytate-modified biochar pyrolyzed at 500℃),and PBC700(phytate-modified biochar pyrolyzed at 700℃)may have metaphosphoric acid linked to oxygen atoms and metaphosphoric acid linked in a bridging manner on the surface of biochar,catalyzing the production of hydroxyl radicals by PMS.PBC700 catalyzes the production of singlet oxygen by PMS through its structural defects,and singlet oxygen is the main catalytic product of PBC700.展开更多
文摘Luminescent solar concentrators (LSCs) with styrene (ST) and methylmethacrylate (MMA) of different percentage as the matrix were prepared by a casting method using ponceau 2R. DSC has been used to compare the thermal stability of the different LSCs. FTIR spectroscopy shows that appearance of -N=N- for ponceau 2R in all ST/MMA matrixes indicating that the highest stability of this kind of dye in these matrixes. The values of the optical band gap (Eg) have been obtained from direct allowed transition before and after the samples have been exposed to sunlight for 9 weeks. Photodegradation studies revealed that the more photostable dye doped in PMMA matrix than in other matrixes. The results showed that the homo PMMA/ponceau 2R system has the highest fluorescence quantum yield (Qf). Therefore this sample can be selected for field performance of fluorescent solar collectors. The photovoltaic cell coupled with homo PMMA/2R LSC shows a maximum efficiency, 2% compared to the normal one.
基金the 13th Five-Year key research program of China(2017YFB0308303)Key Research&Development programs of Shaanxi Province(2018SF363)Key Research&Development programs of Weiyang District,Xian(202043).
文摘The mechanism of oxidation and degradation effect of phytate-modified biochar catalyzed persulfate on Ponceau 2R was investigated.Chemical-structural properties of phytate-modified biochar,such as surface morphology and surface oxygen-containing functional groups were characterized.The results suggest that modified biochar has better oxidation performance than unmodified biochar,and the modified biochar generated at 500℃pyrolysis temperature can catalyze peroxymonosulfate(PMS)system with high efficiency,in large pH and temperature scope.And the degradation mechanism of Ponceau 2R by biochar-catalyzed PMS generation(BC-PMS)system was researched.It revealed that PBC300(phytate-modified biochar pyrolyzed at 300℃),PBC500(phytate-modified biochar pyrolyzed at 500℃),and PBC700(phytate-modified biochar pyrolyzed at 700℃)may have metaphosphoric acid linked to oxygen atoms and metaphosphoric acid linked in a bridging manner on the surface of biochar,catalyzing the production of hydroxyl radicals by PMS.PBC700 catalyzes the production of singlet oxygen by PMS through its structural defects,and singlet oxygen is the main catalytic product of PBC700.