title: Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor.
abstract: Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO(2)/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H(2) generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g(-1) at 0.5 A g(-1) and 287 F g(-1) at 1 A g(-1) are obtained with TiO(2)/Ni(OH)(2) nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application.
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
authors.forename: Xinhui
authors.initials: X
authors.lastname: Xia
authors.forename: Jingshan
authors.initials: J
authors.lastname: Luo
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Zeng
authors.forename: Cao
authors.initials: C
authors.lastname: Guan
authors.forename: Yongqi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jiangping
authors.initials: J
authors.lastname: Tu
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Hong Jin
authors.initials: HJ
authors.lastname: Fan
mesh_terms: D025802:Electric Capacitance; D011211:Electric Power Supplies; D004563:Electrochemistry / Q000295:instrumentation*; D004581:Electronics / Q000295:instrumentation*; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006859:Hydrogen / Q000737:chemistry* / Q000302:isolation & purification; D008027:Light; D010777:Photochemistry / Q000295:instrumentation*; D012993:Solar Energy; D018511:Systems Integration
chemical_list: D006859:Hydrogen