Over the past few decades,I-III-VI quantum dots(QDs)have attracted considerable attention due to their large Stokes shifts,good eco-friendliness,and wide tunable emissions.In this work,a facile microwave-assisted aque...Over the past few decades,I-III-VI quantum dots(QDs)have attracted considerable attention due to their large Stokes shifts,good eco-friendliness,and wide tunable emissions.In this work,a facile microwave-assisted aqueous route using glutathione(GSH)and citric acid(CA)as dual stabilizers is introduced to synthesize AgInGaS/ZnS(AIGS/ZnS)core/shell QDs.An exceptional photoluminescence quantum yield(PL QY)as high as 79%is successfully achieved,boosting the best performance of water-dispersible AIGS QDs.By varying the Ag/Ga ratio,the PL peak wavelength can be tuned from 547 to 616 nm,and luminescent hydrogel films with different colors are obtained by embedding AIGS/ZnS QDs in polyacrylamide/poly-vinyl alcohol(PAAm/PVA)hydrogels.The white light-emitting diode(WLED)with a high color rendering index(CRI)of 92.1(R_(9)=92.0)and a correlated color temperature(CCT)of 3022 K is fabricated using QDs-PAAm/PVA hydrogel films in combination with a blue InGaN LED chip,indicating that the as-prepared QDs are competitive color-conversion materials for WLEDs.展开更多
采用水热合成法制备核壳结构Zn/HZSM-5_((Si/Al=25))@HZSM-5_((Si/Al=200))催化剂,并考察其甲醇制芳烃(Methanol to Aromatics,MTA)反应性能,重点研究壳层包覆对催化剂积碳行为及催化寿命的影响。结果表明,高Si/Al壳层催化剂其低酸量可...采用水热合成法制备核壳结构Zn/HZSM-5_((Si/Al=25))@HZSM-5_((Si/Al=200))催化剂,并考察其甲醇制芳烃(Methanol to Aromatics,MTA)反应性能,重点研究壳层包覆对催化剂积碳行为及催化寿命的影响。结果表明,高Si/Al壳层催化剂其低酸量可抑制含氧积碳生成;壳层对核层的包覆作用可从根本上阻断核层催化剂上含氧积碳的生成;核壳结构的构筑可调变催化剂积碳行为,催化剂失活速率降低,催化稳定性和芳构化性能明显增强,在反应温度T=400℃,甲醇空速WHSV=1.2 h^(-1)的反应条件下,Zn/HZSM-5@HZSM-5核壳催化剂的催化寿命达210 h,起始轻质芳烃(BTX)选择性达46.2%且反应138 h后仍高达20%以上。展开更多
基金supported by the National Natural Science Foundation of China(NSFC,No.62074044,NSFC,No.61904036),Zhongshan-Fudan Joint Innovation Center,Jihua Laboratory Projects of Guangdong Province(X190111UZ190)Shanghai Post-doctoral Excellence Program(2021016)Shanghai Rising-Star program(22YF1402000).
文摘Over the past few decades,I-III-VI quantum dots(QDs)have attracted considerable attention due to their large Stokes shifts,good eco-friendliness,and wide tunable emissions.In this work,a facile microwave-assisted aqueous route using glutathione(GSH)and citric acid(CA)as dual stabilizers is introduced to synthesize AgInGaS/ZnS(AIGS/ZnS)core/shell QDs.An exceptional photoluminescence quantum yield(PL QY)as high as 79%is successfully achieved,boosting the best performance of water-dispersible AIGS QDs.By varying the Ag/Ga ratio,the PL peak wavelength can be tuned from 547 to 616 nm,and luminescent hydrogel films with different colors are obtained by embedding AIGS/ZnS QDs in polyacrylamide/poly-vinyl alcohol(PAAm/PVA)hydrogels.The white light-emitting diode(WLED)with a high color rendering index(CRI)of 92.1(R_(9)=92.0)and a correlated color temperature(CCT)of 3022 K is fabricated using QDs-PAAm/PVA hydrogel films in combination with a blue InGaN LED chip,indicating that the as-prepared QDs are competitive color-conversion materials for WLEDs.
