Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical proper...Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical property,high stability and biocompatibility.In particular,they were widely used in environmental field,such as photocatalysis,catalytic combustion,catalytic oxidation and sensors.In this review,the recent progresses in the synthesis of 3DOM perovskite materials and their environmental applications are summarized.The advantages and the promoting mechanisms of 3DOM perovskite materials for different applications are discussed in detail.Subsequently,the challenges and perspectives on the topic are proposed.展开更多
NH_(3)-SCR is an effective mean of NOxremoval in the non-electric industry, however, the high activation temperature and poor H_(2)O resistance of SCR catalysts posed a barrier to its application. In this work, a seri...NH_(3)-SCR is an effective mean of NOxremoval in the non-electric industry, however, the high activation temperature and poor H_(2)O resistance of SCR catalysts posed a barrier to its application. In this work, a series of three-dimensionally ordered macroporous(3DOM) catalysts were synthesized via a colloidal crystal template(CCT) method, and various characterizations were carried out to explore the physicochemical property of catalysts. The experiment results reveal that Ce_(0.2)Mn_(0.2)/3DOM-TiO_(2) catalyst presents the excellent low-temperature catalytic activity of nearly 100% at 100℃. Furthermore, the enhanced H_(2)O resistance is achieved, certified by the unaffected NO remove at 150℃ in the participation of 15 vol% H_(2)O. The characterizations results exhibit that the improved dispersion of the active component and enhanced redox ability are conducive to the low-temperature catalytic activity. N_(2) adsorption and desorption experiments indicate that catalyst with 3DOM support possesses a larger pore diameter and specific surface area, which may weaken the condensation of H_(2)O in the microporosity of catalysts and improved the H_(2)O resistance of the catalyst. In situ DRIFTS results manifest that Ce_(0.2)Mn_(0.2)/3DOM-TiO_(2) catalyst could not only absorb more NH_(3) and generate more surface-active sites, but inhibit the competitive adsorption between H_(2)O and SCR reactants.展开更多
In this study,a g-C_(3)N_(4)-Cu_(2)O-TiO_(2) photocatalyst with a novel three-dimensional ordered macroporous(3DOM)structure was successfully prepared using a sacrificial template strategy and a photodeposition method...In this study,a g-C_(3)N_(4)-Cu_(2)O-TiO_(2) photocatalyst with a novel three-dimensional ordered macroporous(3DOM)structure was successfully prepared using a sacrificial template strategy and a photodeposition method.The influence of the special porous structure with cross pore channels on the photocatalytic properties of the as-prepared sample was studied in detail.Compared with the original photocatalyst(TiO_(2) with 3 wt%Pt),g-C_(3)N_(4)-Cu_(2)O-TiO_(2) exhibited a higher specific surface area and more active sites,thus accelerating the separation efficiency of the photogenerated electron-hole pair.Consequently,the as-prepared photocatalyst showed good photocatalytic performance,reaching a maximum hydrogen production rate of 12,108μmol g^(-1) h^(-1) and approximately five times higher than that of the pristine comparison sample.The enhanced photoactivity of the g-C_(3)N_(4)-Cu_(2)O-TiO_(2) heterojunction can be ascribed to its double p-n heterojunction and robust porous structure,where the photodeposited Cu_(2)O plays a synergistic catalytic role in the photocatalytic process and the outer clad g-C_(3)N_(4) layer prevents Cu_(2)O oxidation.Additionally,the possible photocatalytic mechanism was briefly discussed based on the experimental results.This work identifies viable pathways for developing low-cost heterojunction photocatalysts with highly efficient photocatalytic activity toward improved solar energy conversion.展开更多
A stable 3DOM CeO2 with well-defined inverse opal microstructure and crystalline walls structure has been successfully synthesized by application of three-dimensional order PMMA beads as templates. Structural feature ...A stable 3DOM CeO2 with well-defined inverse opal microstructure and crystalline walls structure has been successfully synthesized by application of three-dimensional order PMMA beads as templates. Structural feature of products was characterized by using SEM, DTA-TG XRD.展开更多
It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(...It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application.展开更多
基金supported by the Tianjin Municipal Natural Science Foundation(17JCYBJC22600)the Fundamental Research Funds for the Central Universities~~
文摘Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical property,high stability and biocompatibility.In particular,they were widely used in environmental field,such as photocatalysis,catalytic combustion,catalytic oxidation and sensors.In this review,the recent progresses in the synthesis of 3DOM perovskite materials and their environmental applications are summarized.The advantages and the promoting mechanisms of 3DOM perovskite materials for different applications are discussed in detail.Subsequently,the challenges and perspectives on the topic are proposed.
基金Project supported by National Key Research and Development Program of China(2021YFB3500601)。
文摘NH_(3)-SCR is an effective mean of NOxremoval in the non-electric industry, however, the high activation temperature and poor H_(2)O resistance of SCR catalysts posed a barrier to its application. In this work, a series of three-dimensionally ordered macroporous(3DOM) catalysts were synthesized via a colloidal crystal template(CCT) method, and various characterizations were carried out to explore the physicochemical property of catalysts. The experiment results reveal that Ce_(0.2)Mn_(0.2)/3DOM-TiO_(2) catalyst presents the excellent low-temperature catalytic activity of nearly 100% at 100℃. Furthermore, the enhanced H_(2)O resistance is achieved, certified by the unaffected NO remove at 150℃ in the participation of 15 vol% H_(2)O. The characterizations results exhibit that the improved dispersion of the active component and enhanced redox ability are conducive to the low-temperature catalytic activity. N_(2) adsorption and desorption experiments indicate that catalyst with 3DOM support possesses a larger pore diameter and specific surface area, which may weaken the condensation of H_(2)O in the microporosity of catalysts and improved the H_(2)O resistance of the catalyst. In situ DRIFTS results manifest that Ce_(0.2)Mn_(0.2)/3DOM-TiO_(2) catalyst could not only absorb more NH_(3) and generate more surface-active sites, but inhibit the competitive adsorption between H_(2)O and SCR reactants.
基金funded by the National Key Research and Development Program of China (2016YFC0300200)the National Natural Science Foundation of China (21975229)the Natural Science Foundation of Zhejiang Province (Y19B060003)
文摘In this study,a g-C_(3)N_(4)-Cu_(2)O-TiO_(2) photocatalyst with a novel three-dimensional ordered macroporous(3DOM)structure was successfully prepared using a sacrificial template strategy and a photodeposition method.The influence of the special porous structure with cross pore channels on the photocatalytic properties of the as-prepared sample was studied in detail.Compared with the original photocatalyst(TiO_(2) with 3 wt%Pt),g-C_(3)N_(4)-Cu_(2)O-TiO_(2) exhibited a higher specific surface area and more active sites,thus accelerating the separation efficiency of the photogenerated electron-hole pair.Consequently,the as-prepared photocatalyst showed good photocatalytic performance,reaching a maximum hydrogen production rate of 12,108μmol g^(-1) h^(-1) and approximately five times higher than that of the pristine comparison sample.The enhanced photoactivity of the g-C_(3)N_(4)-Cu_(2)O-TiO_(2) heterojunction can be ascribed to its double p-n heterojunction and robust porous structure,where the photodeposited Cu_(2)O plays a synergistic catalytic role in the photocatalytic process and the outer clad g-C_(3)N_(4) layer prevents Cu_(2)O oxidation.Additionally,the possible photocatalytic mechanism was briefly discussed based on the experimental results.This work identifies viable pathways for developing low-cost heterojunction photocatalysts with highly efficient photocatalytic activity toward improved solar energy conversion.
基金The financial supports from The National Natural Science Foundation of China(20163002)Natural Science Foundation of Yunnan Province(2003E0005Z)are gratefully acknowledged.
文摘A stable 3DOM CeO2 with well-defined inverse opal microstructure and crystalline walls structure has been successfully synthesized by application of three-dimensional order PMMA beads as templates. Structural feature of products was characterized by using SEM, DTA-TG XRD.
基金supported by the National Key Research and Development Program of China(Nos.2022YFB3504100,2022YFB3506200)the National Natural Science Foundation of China(Nos.22208373,22376217)+1 种基金the Beijing Nova Program(No.20220484215)the Science Foundation of China University of Petroleum,Beijing(No.2462023YJRC030)。
文摘It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application.