7 research outputs found
Design of SnO2 Aggregate/Nanosheet Composite Structures Based on Function-Matching Strategy for Enhanced Dye-Sensitized Solar Cell Performance
Hierarchical SnO2 nanocrystallites aggregates (NAs) were prepared with a simple room temperature–based aqueous solution method followed by simple freeze-drying treatment. The as-prepared SnO2 NAs were subsequently combined with SnO2 nanosheet–based structures from the viewpoint of a function-matching strategy, and under an optimized condition, a power conversion efficiency (PCE) of 5.59% was obtained for the resultant hybrid photoanode, a remarkable 60% enhancement compared to that of dye-sensitized solar cells (DSCs) fabricated with bare SnO2 NAs architecture. The significantly enhanced efficiency can be attributed to the combination of the desirable electron transport property obtained by the intentionally introduced SnO2 nanosheets (NSs) and the effectively retained inherent characteristics of SnO2 NAs, i.e., large surface area and strong light-scattering effect. This work provides a promising approach for the rapid development of highly efficient SnO2 photoanode film-based DSCs with the properties of simplicity of operation and control over the photoanode composition
Aqueous Solution-Processed Multifunctional SnO<sub>2</sub> Aggregates for Highly Efficient Dye-Sensitized Solar Cells
A room temperature
based environmentally friendly aqueous solution
synthesis route was developed to fabricate highly dispersed small
SnO<sub>2</sub> nanoparticles (3–5 nm) without the application
of any pressurized reaction vessel or organic solvents. The subsequent
treatments, that is, dialyzing and freezing, allow for the acquision
of dual-function nanostructures with sheet-like feature and large
aspect ratio except for the ordinary irregular aggregates. Dye-sensitized
solar cells (DSCs) constructed with the resultant multifunctional
SnO<sub>2</sub> showed an outstanding photovoltaic conversion efficiency
(PCE) of 6.92% and an unexpected <i>J</i><sub>SC</sub> of
19.5 mA cm<sup>–2</sup> at an optimized thickness of 14.1 μm.
The excellent performance can be ascribed to the effective coordination
of the favorable features (i.e., strong light scattering, large dye
loading capability, and fast electron transport) via rational film
thickness control as indicated by diffused reflectance spectra, UV–vis
absorption spectra, and electrochemical impedance spectroscopy (EIS)