ABSTRACT
Exploring novel photoactive materials with high photoelectric conversion efficiency plays a crucial role in enhancing the analytical performance of paper-based photoelectrochemical (PEC) biosensor. SnO2, which possesses higher photostability and electron mobility, can be regarded as a promising photoactive material. Herein, paper-based one dimensional (1D) domed SnO2 nanotubes (NTs) have been developed with the template-consumption strategy. What's more, their growth mechanism has also been proposed based on the controllable experiments. At first, the paper-based 1D ZnO nanorods (NRs) as the typical amphoteric oxide are prepared and serve as the sacrifice templates which can be etched by the generated alkaline environment during the formation of SnO2. At a certain stage, all the ZnO NRs can be completely etched by controlling the experimental conditions, resulting in the forming of vertically distributed hollow SnO2 NTs. Furthermore, the Sn self-doping strategy is also proposed to suppress the recombination of charge carriers and broaden the light response range by introducing the impurity energy levels. Profiting from such doping strategy, the prominent photocurrent signal is obtained compared with pure paper-based SnO2 NTs. Ultimately, an innovative visible light responsive paper-based Sn-doping SnO2-x NTs are developed and employed as the photoelectrode for the PEC biosensor using the alpha fetoprotein (AFP) as the model analyte. Under the optimal conditions, the ultrasensitive AFP sensing is realized with the linear range and detection limitation of 10 pg mL-1 to 200 ng mL-1 and 3.84 pg mL-1, respectively. This work provides a judiciously strategy for developing novel photoactive materials for paper-based PEC bioanalysis.
Subject(s)
Biosensing Techniques , Nanotubes , Light , OxidesABSTRACT
The title cobalt(II) coordination polymer, poly[[diaquacobalt(II)]-mu4-3,3'-(p-phenylene)diacrylato], [Co(C12H8O4)(H2O)2]n, was obtained by reaction of Co(NO3)(2).6H2O and 3,3'-(p-phenylene)diacrylic acid (H2L) under hydrothermal conditions. Each Co(II) cation sits on a centre of inversion and is hexacoordinated by six O-atom donors in an octahedral geometry. The Co(II) centres are connected by four centrosymmetric L2- anions, resulting in a three-dimensional framework structure. The coordinated water molecules and carboxylate O atoms form hydrogen-bond interactions, stabilizing the structure of the three-dimensional framework. Topologically, the framework represents a rare example of the three-dimensional 4-connected CdSO4 network type. The metal cations and the organic ligand both show in-plane coordination with respect to the extended structure.
ABSTRACT
The complete mol-ecule of the title compound, [MnCl(2)(C(18)H(10)N(4))(2)], is generated by crystallographic twofold symmetry with the Mn atom lying on the rotation axis. The Mn coordination geometry is a distorted cis-MnCl(2)N(4) octa-hedron, arising from two N,N'-bidentate dipyrido[3,2-a:2',3'-c]phenazine (DPPZ) ligands and two chloride ions. In the crystal structure, neighbouring mononuclear units pack together through π-π contacts between the DPPZ rings [shortest centroid-centroid distance = 3.480â (2)â Å], leading to a chain-like structure along [001]. C-Hâ¯Cl hydrogen bonds complete the structure.
