Room Temperature Deposition of Crystalline Nanoporous ZnO Nanostructures for Direct Use as Flexible DSSC Photoanode.
A facile approach to fabricate dye-sensitized solar cells (DSSCs) is demonstrated by depositing (001) oriented zinc oxide (ZnO) nanostructures on both glass and flexible substrates at room temperature using pulsed laser deposition. Unique crystallographic characteristics of ZnO combined with highly non-equilibrium state of pulsed laser-induced ablated species enabled highly crystalline ZnO nanostructures without aid of any chemically induced additives or organic/inorganic impurities at room temperature. Film morphology as well as internal surface area is tailored by varying ambient oxygen pressure and deposition time. It is revealed that the optimization of these two experimental factors was essential for achieving structure providing large surface area as well as efficient charge collection. The DSSCs with optimized ZnO photoanodes showed overall efficiencies of 3.89 and 3.4 % on glass and polyethylene naphthalate substrates, respectively, under AM 1.5G light illumination. The high conversion efficiencies are attributed to elongated electron lifetime and enhanced electrolyte diffusion in the high crystalline ZnO nanostructures, verified by intensity-modulated voltage spectroscopy and electrochemical impedance measurements.
Department of Materials Science Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, South Korea.
Byung Suh
BS
Han
Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA, 15261, USA.
Salim
S
Caliskan
Department of Materials Science Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, South Korea.
Woonbae
W
Sohn
Department of Materials Science Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, South Korea.
Miyoung
M
Kim
Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA, 15261, USA.
Jung-Kun
JK
Lee
Department of Materials Science Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, South Korea. hwjang@snu.ac.kr.
Ho Won
HW
Jang
Dye-sensitized solar cell; Electron recombination; Pulsed laser deposition (PLD); Room temperature; Zinc oxide (ZnO)