title: Improved sensitivity of polychlorinated-biphenyl-orientated porous-ZnO surface photovoltage sensors from chemisorption-formed ZnO-CuPc composites.
abstract: We report a new mechanism for the enhancement of porous-ZnO surface photovoltage (SPV) response to polychlorinated biphenyls (PCBs, a notorious class of persistent organic pollutants as global environmental hazard) based on copper phthalocyanine (CuPc) chemisorptive bonding on porous-ZnO. A new ZnO-CuPc composite is formed on the porous-ZnO surface due to the interaction between the surface ZnO and CuPc, with its valence band (VB) energy level being higher than that of the pristine porous-ZnO. So that the efficiency of the photogenerated-electron transfer from the composite VB to the adjacent ZnO's surface states is drastically increased due to the reduced energy gap between the transition states. As a result, the sensitivity of the PCB-orientated SPV sensor is much improved by showing amplified variation of the SPV-signals perturbed by PCBs adsorbed on the ZnO-CuPc@porous-ZnO sensitive material.
authors.affiliation: Key Laboratory of Materials Physics, and Anhui Key Laboratory of Nanomaterials and Nanostructures, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P. R. China.
authors.forename: Mingtao
authors.initials: M
authors.lastname: Li
authors.affiliation: 1] Key Laboratory of Materials Physics, and Anhui Key Laboratory of Nanomaterials and Nanostructures, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P. R. China [2] University of Science & Technology of China, Hefei 230026, P. R. China.
authors.forename: Guowen
authors.initials: G
authors.lastname: Meng
authors.affiliation: Key Laboratory of Ion Beam Bioengineering, Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Huang
authors.affiliation: High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, P. R. China.
authors.forename: Shile
authors.initials: S
authors.lastname: Zhang