Direct X-ray detectors,which directly convert X-rays into electrical signals through semiconductors,have higher space solution than scintillator-mediated indirect X-ray ones and are high desirable for early cancer det...Direct X-ray detectors,which directly convert X-rays into electrical signals through semiconductors,have higher space solution than scintillator-mediated indirect X-ray ones and are high desirable for early cancer detection and other applications,but the mainstream commercialα-Se detector is still largely limited by high production costs,large leakage current and low stability.This article reports an easily prepared,stable radiochromic semiconductive metal–organic framework(MOF),(MV)[Cd_(3)(tdc)_(4)]·2H_(2)O(RCS-1,H_(2)tdc=2,5-thiophenedicarboxylic acid;MV^(2+)=methyl viologen cation)with direct X-ray detecting ability.With a large bulk resistivity of 8.40×10^(9)Ωcm,this material ensures minimal dark current and low noise for X-ray detection.Additionally,it exhibits higher sensitivity to W KαX-rays(98.58μC Gy^(-1)cm^(-2))thanα-Se(~20μC Gy^(-1)cm^(-2)).Meanwhile,unlike most reported direct X-ray detecting semiconductors,compound RCS-1 shows remarkable color change upon X-ray irradiation owing to the presence of photochromism-active viologen cations.This feature offers an appealing visual detecting ability to direct X-ray detectors that provide only the electrical signals.展开更多
Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc...Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc.).Previous synthetic methods resulted in low switching contrasts(<two times)or they tended to be limited significantly in solid matrixes due to large structural changes.The photoinduced electron-transfer(PIET)method avoids the influence of stereo space in solid matrixes and capable of achieving high switching contrasts.For the first time,we applied the PIET strategy to design lightresponsive proton conductors to achieve the hitherto largest gain of proton conductivity(ca.54 times)for light-responsive proton conductors in one crystalline photochromic viologen-based H-bonded supramolecule.The weakening of hydrogen-bonding interactions in the proton-transport path after PIET accounted for an increased proton conductivity.These findings would inspire the exploration of photon conductors that display higher proton conductivities or switchable smart systems with high contrasts.展开更多
基金financial support by the National Key Research and Development Program of Ministry of Science and Technology(No.2021YFB3801604)the National Natural Science Foundation(Nos.22073102,21827813,21921001)of China。
文摘Direct X-ray detectors,which directly convert X-rays into electrical signals through semiconductors,have higher space solution than scintillator-mediated indirect X-ray ones and are high desirable for early cancer detection and other applications,but the mainstream commercialα-Se detector is still largely limited by high production costs,large leakage current and low stability.This article reports an easily prepared,stable radiochromic semiconductive metal–organic framework(MOF),(MV)[Cd_(3)(tdc)_(4)]·2H_(2)O(RCS-1,H_(2)tdc=2,5-thiophenedicarboxylic acid;MV^(2+)=methyl viologen cation)with direct X-ray detecting ability.With a large bulk resistivity of 8.40×10^(9)Ωcm,this material ensures minimal dark current and low noise for X-ray detection.Additionally,it exhibits higher sensitivity to W KαX-rays(98.58μC Gy^(-1)cm^(-2))thanα-Se(~20μC Gy^(-1)cm^(-2)).Meanwhile,unlike most reported direct X-ray detecting semiconductors,compound RCS-1 shows remarkable color change upon X-ray irradiation owing to the presence of photochromism-active viologen cations.This feature offers an appealing visual detecting ability to direct X-ray detectors that provide only the electrical signals.
基金supported by the National Natural Science Foundation of China(nos.91545201,21827813,22001011,and 22001037)the Strategic Priority Research Program of the Chinese Academy of Sciences(nos.XDB20010100 and YJKYYQ20180006)the Key Research Program of Frontier Science,Chinese Academy of Sciences(no.QYZDB-SSW-SLH020).
文摘Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc.).Previous synthetic methods resulted in low switching contrasts(<two times)or they tended to be limited significantly in solid matrixes due to large structural changes.The photoinduced electron-transfer(PIET)method avoids the influence of stereo space in solid matrixes and capable of achieving high switching contrasts.For the first time,we applied the PIET strategy to design lightresponsive proton conductors to achieve the hitherto largest gain of proton conductivity(ca.54 times)for light-responsive proton conductors in one crystalline photochromic viologen-based H-bonded supramolecule.The weakening of hydrogen-bonding interactions in the proton-transport path after PIET accounted for an increased proton conductivity.These findings would inspire the exploration of photon conductors that display higher proton conductivities or switchable smart systems with high contrasts.
