Layered hybrid perovskite ferroelectrics have made significant strides in high-performance X-ray detection,attributed to their polarization-induced large built-in electric fields and excellent carrier mobility.However...Layered hybrid perovskite ferroelectrics have made significant strides in high-performance X-ray detection,attributed to their polarization-induced large built-in electric fields and excellent carrier mobility.However,most reported layered hybrid perovskite ferroelectrics rely on environmentally hazardous lead halides,which limits their broader application.Recently developed hybrid double perovskites offer promising alternatives for green self-driven X-ray detection.Herein,we explore the bulk photovoltaic effect in a two-dimensional multilayered double perovskite ferroelectric CHMA_(2)CsAgBiBr_(7)(CCAB,CHMA+=cyclohexylmethylammonium)for self-driven X-ray detection.Due to its multilayer structure,CCAB exhibits a largeμτproduct of 3.3×10^(-3)cm2 V^(-1),which is comparable to the three-dimensional double perovskite Cs_(2)AgBiBr_(6).Specifically,the X-ray detector exhibits a photovoltage of 0.84 V under X-ray irradiation,ensuring the capability to convert X-rays into electric signals without bias.Additionally,CCAB exhibits a high sensitivity up to 120μC Gy^(-1)cm^(-2)and a low detection limit down to 103 nGy s^(-1)in the self-driven mode.Our work highlights the potential of lead-free multilayered double perovskite ferroelectrics for achieving high-performance self-driven X-ray detection,paving the way for practical applications of layered hybrid perovskite ferroelectrics in this field.展开更多
Visible and even infrared(IR)light-initiated hot electrons of graphene(Gr)catalysts are a promising driven power for green,safe,and sustainable H2O2 synthesis and organic synthesis without the limitation of bandgap-do...Visible and even infrared(IR)light-initiated hot electrons of graphene(Gr)catalysts are a promising driven power for green,safe,and sustainable H2O2 synthesis and organic synthesis without the limitation of bandgap-dominated narrow light absorption to visible light confronted by conventional photocatalyst.However,the life time of photogenerated hot electrons is too short to be efficiently used for various photocatalytic reactions.Here,we proposed a straightforward method to prolong the lifetime of photogenerated hot electrons from graphene by tuning the Schottky barrier at Gr/rutile interface to facilitate the hot electron injection.The rational design of Gr-coated TiO2 heterojunctions with interface synergy-induced decrease in the formation energy of the rutile phase makes the phase transfer of TiO2 support proceed smoothly and rapidly via ball milling.The optimized Gr/rutile dyad could provide a H2O2 yield of 1.05 mM·g-1·h-1 under visible light irradiation(λ≥400 nm),which is 30 times of the state-of-the-art noble-metal-free titanium oxide-based photocatalyst,and even achieves a H2O2 yield of 0.39 mM·g-1·h-1 on photoexcitation by near-infrared-region light(~800 nm).展开更多
基金supported by the National Natural Science Foundation of China(22435005,22193042,22125110,and U21A2069)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SLH024)the Youth Innovation Promotion of Chinese Academy of Sciences(2019301,Y202069,and 2020307).
文摘Layered hybrid perovskite ferroelectrics have made significant strides in high-performance X-ray detection,attributed to their polarization-induced large built-in electric fields and excellent carrier mobility.However,most reported layered hybrid perovskite ferroelectrics rely on environmentally hazardous lead halides,which limits their broader application.Recently developed hybrid double perovskites offer promising alternatives for green self-driven X-ray detection.Herein,we explore the bulk photovoltaic effect in a two-dimensional multilayered double perovskite ferroelectric CHMA_(2)CsAgBiBr_(7)(CCAB,CHMA+=cyclohexylmethylammonium)for self-driven X-ray detection.Due to its multilayer structure,CCAB exhibits a largeμτproduct of 3.3×10^(-3)cm2 V^(-1),which is comparable to the three-dimensional double perovskite Cs_(2)AgBiBr_(6).Specifically,the X-ray detector exhibits a photovoltage of 0.84 V under X-ray irradiation,ensuring the capability to convert X-rays into electric signals without bias.Additionally,CCAB exhibits a high sensitivity up to 120μC Gy^(-1)cm^(-2)and a low detection limit down to 103 nGy s^(-1)in the self-driven mode.Our work highlights the potential of lead-free multilayered double perovskite ferroelectrics for achieving high-performance self-driven X-ray detection,paving the way for practical applications of layered hybrid perovskite ferroelectrics in this field.
基金supported by the National Natural Science Foundation of China(Nos.21737002,21931005,21720102002,and 22071146)Shanghai Science and Technology Committee(Nos.19JC1412600 and 20520711600)the SJTU-MPI partner group.
文摘Visible and even infrared(IR)light-initiated hot electrons of graphene(Gr)catalysts are a promising driven power for green,safe,and sustainable H2O2 synthesis and organic synthesis without the limitation of bandgap-dominated narrow light absorption to visible light confronted by conventional photocatalyst.However,the life time of photogenerated hot electrons is too short to be efficiently used for various photocatalytic reactions.Here,we proposed a straightforward method to prolong the lifetime of photogenerated hot electrons from graphene by tuning the Schottky barrier at Gr/rutile interface to facilitate the hot electron injection.The rational design of Gr-coated TiO2 heterojunctions with interface synergy-induced decrease in the formation energy of the rutile phase makes the phase transfer of TiO2 support proceed smoothly and rapidly via ball milling.The optimized Gr/rutile dyad could provide a H2O2 yield of 1.05 mM·g-1·h-1 under visible light irradiation(λ≥400 nm),which is 30 times of the state-of-the-art noble-metal-free titanium oxide-based photocatalyst,and even achieves a H2O2 yield of 0.39 mM·g-1·h-1 on photoexcitation by near-infrared-region light(~800 nm).
