Synthesis of hierarchical structure cuprous oxide by a novel two-step hydrothermal method and the effect of its addition on the photovoltaic properties of ZnO-based dye-sensitized solar cells

• Published in: Journal of alloys and compounds Vol. 721; pp. 8 - 17
• Main Authors: Zhou, Xiaofeng, Xie, Yahong, Ma, Junhong, Mi, Hongyu, Yang, Jianya, Cheng, Jian, Hoang, Tuan K.A.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.10.2017; Elsevier BV
• Subjects: Anchoring; Band gap; Bilayer; Charge transfer; Chemical synthesis; Composite materials; Copper oxides; Cu2O; Dye-sensitized solar cell; Dye-sensitized solar cells; Dyes; Hot water; Hot water bath; Load resistance; Offsets; Particle physics; Particulate composites; Photovoltaic cells; Porosity; Shortages; Structural hierarchy; Zinc oxide; ZnO; Dye-sensitized solar cell; Hot water bath; ZnO; Bilayer; Cu2O
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.05.334

Cuprite Cu2O particles with different morphologies and very narrow band gap were synthesized through combining a hot water bath process with a post calcination process. The ZnO was prepared by using a simple solid-state method. When using the ZnO/Cu2O composite as the photoanode, the ZnO/Cu2O-based dye-sensitized solar cells (DSSCs) yielded a conversion efficiency of 6.94% at the optimized polyhedron Cu2O addition amounts of 0.25 wt%, which is improved by 23.93% compared with the performance of the pure ZnO-based DSSCs (5.60%). After introducing a ZnO buffer layer, the obtained bilayer ZnO/Cu2O-based DSSCs achieved a significantly elevated efficiency up to 7.02%, which corresponds to a 24.03% improvement compared with the pure bilayer-based one. This improvement can be attributed to the large specific surface area and pore structure of ZnO/Cu2O composite materials and the conductivity of Cu2O, which offsets the inherent shortages of ZnO of lower anchoring site density and poor conductivity, and generates some additional advantages, such as a lower charge transfer resistance, higher dye-loading quantity, longer electron lifetime, and reduced charge recombination. The ZnO-based dye-sensitized solar cell of addition cuprite Cu2O, which induced bridging character was possibly related to its ability to inhibit the inherent shortages of ZnO electrode, and generate a lower charge transfer resistance, abudant dye-loading quantity, longer electron lifetime, and reduced charge recombination. [Display omitted]