CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)h...CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr composite.The as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,respectively.The introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) molecules.The metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and CH_(4).The possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR spectra.This work offers a new possibility for the preparation of advanced photocatalysts.展开更多
A Co_(3)O_(4)/BiOBr heterojunction was synthesized via a facile one-step solvothermal method for highly selec-tive photocatalytic CO_(2)reduction.The optimized Co_(3)O_(4)/BiOBr-0.8 catalyst exhibited CO and CH_(4)evo...A Co_(3)O_(4)/BiOBr heterojunction was synthesized via a facile one-step solvothermal method for highly selec-tive photocatalytic CO_(2)reduction.The optimized Co_(3)O_(4)/BiOBr-0.8 catalyst exhibited CO and CH_(4)evolution rates of 112.2 and 5.5µmol·g^(-1)·h^(-1),respectively,representing 6.3-fold and 3.9-fold enhancements over pristine BiOBr.The heterojunction demonstrated broadened light absorption,enhanced photoelectrochemical activity,reduced charge-transfer resistance,and improved separation efficiency of photogenerated carriers(e^(-)/h^(+)).These synergistic effects were attributed to the formation of a Z-scheme heterostructure,which facilitated solar energy utilization and electron reduction capacity while suppressing carrier recombination.展开更多
The utilization of an efficient photocatalyst is crucial for the photocatalytic degradation of antibiotics in water through visible light,which is an imperative requirement for the remediation of water environments.In...The utilization of an efficient photocatalyst is crucial for the photocatalytic degradation of antibiotics in water through visible light,which is an imperative requirement for the remediation of water environments.In this study,a novel Cu-CeO_(2)/BiOBr Z-type heterojunction was synthesized by calcination and hydrothermal methods,and the degradation rate of sulfathiazole(STZ)antibiotic solution was studied using simulated illumination(300 W xenon lamp).The results indicated that 3%Cu-CeO_(2)/BiOBr achieved a degradation rate of 92.3%within 90 min when treating 20 mg/L STZ solution,demonstrating its potential for practical water treatment applications.Characterization using various chemical instruments revealed that 3%Cu-CeO_(2)/Bi OBr exhibited the lowest electron-hole recombination rate and electron transfer resistance.Furthermore,the utilization of ESR data and quenching experiments has substantiated the involvement of hydroxyl radicals(·OH)and superoxide radicals(·O_(2)^(-))as the primary active species.Consequently,a plausible degradation mechanism has been inferred.These findings offer a prospective approach for the development of heterojunction materials with appropriate band matching.展开更多
Although defect engineering has been widely used to boost catalytic CO_(2) photoreduction,the piezoelectric polarized properties induced by structure changes through introducing defects are always ignored.Here we repo...Although defect engineering has been widely used to boost catalytic CO_(2) photoreduction,the piezoelectric polarized properties induced by structure changes through introducing defects are always ignored.Here we report a new kind of bismuth oxybromide(BiOBr,BOB)with piezoelectric property regulated by oxygen vacancies(OVs).Compared with pure BOB,BOB with OVs(BOB-OV)could enhance photocatalytic CO_(2) reduction efficiency under the ultrasonic force,achieving durable CO_(2) reduction process to superior production rates of CO(54.4μmol g^(-1) h^(-1))with a high selectivity(92%).Moderate OVs concentration changed the degree of Bi-Br stretching in the BOB-OV to produce strong dipole moments,which endowed BOB-OV with strong spontaneous piezoelectric polarization ability under external force.Ultrasonic piezoelectric effects were innovatively integrated into the photocatalytic reaction,which not only provided an alternating force field to modulate the spontaneous polarization of BOB-OV,thereby maintaining efficient photogenerated charge separation,but also lowered the reaction energy barrier of CO_(2) by high stress,ultimately improving CO product selectivity.This study is the first to leverage OVs-induced piezoelectric polarization effects to enhance the performance and product selectivity of photocatalytic CO_(2) reduction,providing new directions and insights for defect engineering to contribute to photocatalysis.展开更多
The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H_(2)O_(2)pro...The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H_(2)O_(2)production.In this investigation,an innovative 2D/2D g-C_(3)N_(4)/BiOBr S-scheme heterojunction was meticulously engineered through an in situ growth methodology.The synthetic composites exhibit boosted H_(2)O_(2)production activity,achieving a peak generation rate of 392μmol L^(-1)h^(-1),approximately 8.7-fold and 2.1-fold increase over the pristine BiOBr and g-C_(3)N_(4),respectively.Such a superior activity should be attributed to the highly efficient charge separation and migration mechanisms,along with the sustained robust redox capability of S-scheme heterostructure,which are verified by time-resolved photoluminescence spectroscopy,photocurrent test and electron paramagnetic resonance measurements.Furthermore,the interfacial electric field induced S-scheme charge transfer mechanism between g-C_(3)N_(4)and BiOBr is systematically certificated by in situ irradiated X-ray photoelectron spectroscopy and density functional theory calculation.This research offers a comprehensive protocol for the systematic development and construction of highly efficient S-scheme heterojunction photocatalysts,specifically tailored for enhanced H_(2)O_(2)production.展开更多
基金financially supported by National Natural Science Foundation of China(Nos.22138011,22108106 and 22108108)China Postdoctoral Science Foundation(Nos.2022M721380 and 2020M680065)Hong Kong Scholar Program(XJ2021021).
文摘CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr composite.The as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,respectively.The introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) molecules.The metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and CH_(4).The possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR spectra.This work offers a new possibility for the preparation of advanced photocatalysts.
文摘A Co_(3)O_(4)/BiOBr heterojunction was synthesized via a facile one-step solvothermal method for highly selec-tive photocatalytic CO_(2)reduction.The optimized Co_(3)O_(4)/BiOBr-0.8 catalyst exhibited CO and CH_(4)evolution rates of 112.2 and 5.5µmol·g^(-1)·h^(-1),respectively,representing 6.3-fold and 3.9-fold enhancements over pristine BiOBr.The heterojunction demonstrated broadened light absorption,enhanced photoelectrochemical activity,reduced charge-transfer resistance,and improved separation efficiency of photogenerated carriers(e^(-)/h^(+)).These synergistic effects were attributed to the formation of a Z-scheme heterostructure,which facilitated solar energy utilization and electron reduction capacity while suppressing carrier recombination.
基金supported by the National Natural Science Foundation of China(Nos.21471103,52372212)。
文摘The utilization of an efficient photocatalyst is crucial for the photocatalytic degradation of antibiotics in water through visible light,which is an imperative requirement for the remediation of water environments.In this study,a novel Cu-CeO_(2)/BiOBr Z-type heterojunction was synthesized by calcination and hydrothermal methods,and the degradation rate of sulfathiazole(STZ)antibiotic solution was studied using simulated illumination(300 W xenon lamp).The results indicated that 3%Cu-CeO_(2)/BiOBr achieved a degradation rate of 92.3%within 90 min when treating 20 mg/L STZ solution,demonstrating its potential for practical water treatment applications.Characterization using various chemical instruments revealed that 3%Cu-CeO_(2)/Bi OBr exhibited the lowest electron-hole recombination rate and electron transfer resistance.Furthermore,the utilization of ESR data and quenching experiments has substantiated the involvement of hydroxyl radicals(·OH)and superoxide radicals(·O_(2)^(-))as the primary active species.Consequently,a plausible degradation mechanism has been inferred.These findings offer a prospective approach for the development of heterojunction materials with appropriate band matching.
文摘Although defect engineering has been widely used to boost catalytic CO_(2) photoreduction,the piezoelectric polarized properties induced by structure changes through introducing defects are always ignored.Here we report a new kind of bismuth oxybromide(BiOBr,BOB)with piezoelectric property regulated by oxygen vacancies(OVs).Compared with pure BOB,BOB with OVs(BOB-OV)could enhance photocatalytic CO_(2) reduction efficiency under the ultrasonic force,achieving durable CO_(2) reduction process to superior production rates of CO(54.4μmol g^(-1) h^(-1))with a high selectivity(92%).Moderate OVs concentration changed the degree of Bi-Br stretching in the BOB-OV to produce strong dipole moments,which endowed BOB-OV with strong spontaneous piezoelectric polarization ability under external force.Ultrasonic piezoelectric effects were innovatively integrated into the photocatalytic reaction,which not only provided an alternating force field to modulate the spontaneous polarization of BOB-OV,thereby maintaining efficient photogenerated charge separation,but also lowered the reaction energy barrier of CO_(2) by high stress,ultimately improving CO product selectivity.This study is the first to leverage OVs-induced piezoelectric polarization effects to enhance the performance and product selectivity of photocatalytic CO_(2) reduction,providing new directions and insights for defect engineering to contribute to photocatalysis.
文摘The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H_(2)O_(2)production.In this investigation,an innovative 2D/2D g-C_(3)N_(4)/BiOBr S-scheme heterojunction was meticulously engineered through an in situ growth methodology.The synthetic composites exhibit boosted H_(2)O_(2)production activity,achieving a peak generation rate of 392μmol L^(-1)h^(-1),approximately 8.7-fold and 2.1-fold increase over the pristine BiOBr and g-C_(3)N_(4),respectively.Such a superior activity should be attributed to the highly efficient charge separation and migration mechanisms,along with the sustained robust redox capability of S-scheme heterostructure,which are verified by time-resolved photoluminescence spectroscopy,photocurrent test and electron paramagnetic resonance measurements.Furthermore,the interfacial electric field induced S-scheme charge transfer mechanism between g-C_(3)N_(4)and BiOBr is systematically certificated by in situ irradiated X-ray photoelectron spectroscopy and density functional theory calculation.This research offers a comprehensive protocol for the systematic development and construction of highly efficient S-scheme heterojunction photocatalysts,specifically tailored for enhanced H_(2)O_(2)production.
