Recently,many efforts have been dedicated to construct artificial catalysts with enzyme-like activity.However,it is still a big challenge to endow artificial catalysts with specific substrate selectivity.In this study...Recently,many efforts have been dedicated to construct artificial catalysts with enzyme-like activity.However,it is still a big challenge to endow artificial catalysts with specific substrate selectivity.In this study,we developed a facile strategy to construct a MIL-53(Fe)-based nanocatalyst with designable selectivity in the degradation of oxytetracycline(OTC).Through the Fe–O–P conjunction,oxytetracycline aptamer(OA)can be easily anchored on MIL-53(Fe)to provide the specific site for OTC binding.We verified that the obtained MIL-53(Fe)-Apt nanocatalyst displayed enhanced catalytic ability in the degradation of OTC,whereas obvious suppression toward other substrate analogues.This performance therefore brings about an anticipated selectivity toward OTC.Moreover,we highlighted that the configuration of aptamers on MIL-53(Fe)can be modulated through varying conjunction mode.Structure–function analysis revealed that aptamer configuration affects the local concentration of substrate around catalytic site,which thus decides the catalytic performance toward OTC.This work presented a facile and promising strategy for developing artificial catalysts with designable selectivity.展开更多
MIL-53(Fe)/polyaniline(PANI) composite was prepared by in situ depositing PANI on the surface of MIL-53(Fe) and their catalytic performances on the simultaneous removal of Rh B and Cr(Ⅵ) were investigated. The elimin...MIL-53(Fe)/polyaniline(PANI) composite was prepared by in situ depositing PANI on the surface of MIL-53(Fe) and their catalytic performances on the simultaneous removal of Rh B and Cr(Ⅵ) were investigated. The elimination efficiency of both RhB and Cr(Ⅵ) reached more than 98% under pH = 2 where hydrochloric acid and citric acid were used to adjust the pH. The results indicated that MIL-53(Fe)/PANI revealed an obvious pH response to the degradation of RhB, while citric acid promoted the Cr(Ⅵ)photoreduction. UV–Vis spectra, EIS, and photocurrent response experiments showed that MIL-53(Fe)/PANI had a better light response and carrier migration ability than MIL-53(Fe). The transient absorption spectra also exhibited that the lifetimes of photo-generated carriers were prolonged after the conductive polymer deposition on the MIL-53(Fe) surface. Scavenger experiments demonstrated that the main active species were·O;-and·OH. Combined with activity evaluation results, and the possible photocatalytic mechanism of MIL-53(Fe)/PANI on RhB oxidation and Cr(Ⅵ) reduction was proposed. The addition of conductive polymer can effectively improve the light response of the catalyst under acidic conditions, and meanwhile citric acid also provided a new mediation for the synergistic degradation of multiple pollutants. Good activity and stability of the catalysts made the scale-up purification of acid water feasible under UV–Vis light.展开更多
MIL-53(Fe) was successfully prepared and deposited on the surface carboxylated polyester(PET) fiber by an optimized conventional solvothermal or industrialized high temperature pressure exhaustion(HTPE) process to dev...MIL-53(Fe) was successfully prepared and deposited on the surface carboxylated polyester(PET) fiber by an optimized conventional solvothermal or industrialized high temperature pressure exhaustion(HTPE) process to develop a PET fiber supported MIL-53(Fe) photocatalyst(MIL-Fe@PET) for the degradation of polyvinyl alcohol(PVA) in water under light emitting diode(LED) visible irradiation. On the basis of several characterizations, MIL-Fe@PET was tested for the photocalytic ability and degradation mechanism. It was found that temperature elevation significantly enhanced the formation and deposition of MIL-53(Fe) with better photocatalytic activity. However, higher temperature than 130℃ was not in favor of its photocatalytic activity. Increasing the number of surface carboxyl groups of the modified PET fiber could cause a liner improvement in MIL-53(Fe) loading content and photocatalytic ability. High visible irradiation intensity also dramatically increased photocatalytic ability and PVA degradation efficiency of MIL-Fe@PET. Na_(2)S_(2)O_(8) was used to replace H_(2)O_(2) as electron acceptor for further promoting PVA degradation in this system. MIL-Fe@PET prepared by HTPE process showed higher MIL-53(Fe) loading content and slightly lower PVA degradation efficiency than that prepared by solvothermal process at the same conditions. These findings provided a practical strategy for the large-scale production of the supported MIL-53(Fe) as a photocatalyst in the future.展开更多
基金the National Natural Science Foundation of China(Nos.22178260 and 21676191).
文摘Recently,many efforts have been dedicated to construct artificial catalysts with enzyme-like activity.However,it is still a big challenge to endow artificial catalysts with specific substrate selectivity.In this study,we developed a facile strategy to construct a MIL-53(Fe)-based nanocatalyst with designable selectivity in the degradation of oxytetracycline(OTC).Through the Fe–O–P conjunction,oxytetracycline aptamer(OA)can be easily anchored on MIL-53(Fe)to provide the specific site for OTC binding.We verified that the obtained MIL-53(Fe)-Apt nanocatalyst displayed enhanced catalytic ability in the degradation of OTC,whereas obvious suppression toward other substrate analogues.This performance therefore brings about an anticipated selectivity toward OTC.Moreover,we highlighted that the configuration of aptamers on MIL-53(Fe)can be modulated through varying conjunction mode.Structure–function analysis revealed that aptamer configuration affects the local concentration of substrate around catalytic site,which thus decides the catalytic performance toward OTC.This work presented a facile and promising strategy for developing artificial catalysts with designable selectivity.
基金the financial support from the National Natural Science Foundation of China (Nos. 21908018 and 22078174)Key Technology Research and Development Program of Shandong (No. 2017GSF217008)Qi Lu Young Scholar Start-up Foundation of Shandong University
文摘MIL-53(Fe)/polyaniline(PANI) composite was prepared by in situ depositing PANI on the surface of MIL-53(Fe) and their catalytic performances on the simultaneous removal of Rh B and Cr(Ⅵ) were investigated. The elimination efficiency of both RhB and Cr(Ⅵ) reached more than 98% under pH = 2 where hydrochloric acid and citric acid were used to adjust the pH. The results indicated that MIL-53(Fe)/PANI revealed an obvious pH response to the degradation of RhB, while citric acid promoted the Cr(Ⅵ)photoreduction. UV–Vis spectra, EIS, and photocurrent response experiments showed that MIL-53(Fe)/PANI had a better light response and carrier migration ability than MIL-53(Fe). The transient absorption spectra also exhibited that the lifetimes of photo-generated carriers were prolonged after the conductive polymer deposition on the MIL-53(Fe) surface. Scavenger experiments demonstrated that the main active species were·O;-and·OH. Combined with activity evaluation results, and the possible photocatalytic mechanism of MIL-53(Fe)/PANI on RhB oxidation and Cr(Ⅵ) reduction was proposed. The addition of conductive polymer can effectively improve the light response of the catalyst under acidic conditions, and meanwhile citric acid also provided a new mediation for the synergistic degradation of multiple pollutants. Good activity and stability of the catalysts made the scale-up purification of acid water feasible under UV–Vis light.
基金supported by Innovation&Pioneering Talents Plan of Jiangsu Province(No.2015-340)。
文摘MIL-53(Fe) was successfully prepared and deposited on the surface carboxylated polyester(PET) fiber by an optimized conventional solvothermal or industrialized high temperature pressure exhaustion(HTPE) process to develop a PET fiber supported MIL-53(Fe) photocatalyst(MIL-Fe@PET) for the degradation of polyvinyl alcohol(PVA) in water under light emitting diode(LED) visible irradiation. On the basis of several characterizations, MIL-Fe@PET was tested for the photocalytic ability and degradation mechanism. It was found that temperature elevation significantly enhanced the formation and deposition of MIL-53(Fe) with better photocatalytic activity. However, higher temperature than 130℃ was not in favor of its photocatalytic activity. Increasing the number of surface carboxyl groups of the modified PET fiber could cause a liner improvement in MIL-53(Fe) loading content and photocatalytic ability. High visible irradiation intensity also dramatically increased photocatalytic ability and PVA degradation efficiency of MIL-Fe@PET. Na_(2)S_(2)O_(8) was used to replace H_(2)O_(2) as electron acceptor for further promoting PVA degradation in this system. MIL-Fe@PET prepared by HTPE process showed higher MIL-53(Fe) loading content and slightly lower PVA degradation efficiency than that prepared by solvothermal process at the same conditions. These findings provided a practical strategy for the large-scale production of the supported MIL-53(Fe) as a photocatalyst in the future.
