Tremendous demands for highly sensitive and selective nonenzymatic electrochemical biosensors have motivated intensive research on advanced electrode materials with high electrocatalytic activity. Herein, the 3D-networked CuO@carbon nanowalls/diamond (C/D) architecture is rationally designed, and it demonstrates wide linear range (0.5 × 10 −6 –4 × 10 −3 m ), high sensitivity (1650 µA cm −2 m m −1 ), and low detection limit (0.5 × 10 −6 m ), together with high selectivity, great long-term stability, and good reproducibility in glucose determination. The outstanding performance of the CuO@C/D electrode can be ascribed to the synergistic effect coming from high-electrocatalytic-activity CuO nanoparticles and 3D-networked conductive C/D film. The C/D film is composed of carbon nanowalls and diamond nanoplatelets; and owing to the large surface area, accessible open surfaces, and high electrical conduction, it works as an excellent transducer, greatly accelerating the mass- and charge-transport kinetics of electrocatalytic reaction on the CuO biorecognition element. Besides, the vertical aligned diamond nanoplatelet scaffolds could improve structural and mechanical stability of the designed electrode in long-term performance. The excellent CuO@C/D electrode promises potential application in practical glucose detection, and the strategy proposed here can also be extended to construct other biorecognition elements on the 3D-networked conductive C/D transducer for various high-performance nonenzymatic electrochemical biosensors.
Designing lead-free inorganic perovskite or perovskite-like structure materials and researching the corresponding photoinduced charge carrier dynamics are always promising due to both the environment and power conversion efficiency considerations. In this work, we intelligently employ a bilayer metal Bi/Cu thin film with different atomic ratios as the precursor to fabricate a CuBiI4 perovskite-like film in situ with a controlled Bi gradient at room temperature. This structure can significantly affect the photoinduced charge carrier dynamics of the resulting products. Next, a series of transient surface photovoltage (TSPV) measurements are carried out to investigate the photoinduced charge carrier dynamics of such CuBiI4 and CuBiI4:organic hybrid thin films. The results reveal that the gradually decreasing Bi content from ITO to CuBiI4 can facilitate the photoinduced charge carrier transportation. Finally, a champion PCE of 1.10% is obtained for an ITO/CuBiI4:polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7)/Au solar cell device. In particular, we find an exact negative correlation of the defined parameter L (the defined value for evaluating the photoinduced charge carrier dynamics in TSPV measurements) with the corresponding PCE of various devices for the first time, which may pave a new way for evaluating the potential photoelectric and photovoltaic performances of new materials without the assembly of solar cell devices.
Siyuan Dong,Yingqi Jia,Xiaozhi Xu,Jianeng Luo,Jingbin Han,Xiaoli Sun
Poly(ethylene terephthalate) (PET) generally suffers from low crystallization rate and long molding duration, which as a result limit its application as engineering plastics. To overcome these drawbacks, series of PET/layered double hydroxide (LDH) nanocomposites were prepared by a solution blending process. The effect of metal composition (MgAl and CaAl) and organo-modification (stearic acid intercalated) for LDH fillers on the crystallization behavior of the nanocomposites was investigated. It was revealed that, compared with PET/CaAl-LDH, the PET/MgAl-LDH nanocomposite exhibits a higher crystallization temperature and faster crystallization rate, which is associated with the superior nucleation ability of MgAl-LDH. The nucleation mechanism of PET induced by LDHs was explored by means of Avrami equation and theory of Hoffman-Lauritzen, pointing out that the incorporation of LDHs reduce the free energy of nucleation and the fold surface free energy of PET. In order to improve the compatibility between LDH and PET, stearic acid (SA) intercalated MgAl-LDH was prepared and filled into PET matrix. The resultant PET/MgAl-LDH-SA shows a further enhanced crystallization temperature and accelerated crystallization rate, in comparison with PET/MgAl-LDH nanocomposites. In addition, the thermal stability, gas barrier and mechanical properties of PET/LDH composites were improved upon incorporation of LDH fillers.
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