High-Density Vertically Aligned ZnO Rods with a Multistage Terrace Structure and Their Improved Solar Cell Efficiency

Abstract

This work reports a solution-based approach to grow high-density vertically aligned ZnO rod arrays with a multistage terrace structure (HDVAMT) on Au nanoparticle covered glass substrates. The solar cell performance of HDVAMT is 10 times better than that of the disordered ZnO due to the much higher short circuit current (J sc ). This significant improvement of J sc is attributed to two factors: the vertically aligned structure, which provides smoother electron transport channels, and the high density of the rods with the multistage terrace structure, which provides a higher surface area for the dye adsorption. A tentative growth mechanism is proposed.

ZnO Nanostructures for Dye‐Sensitized Solar Cells

“…For example, one study found that a ZnO nanorod array led to a ten-fold increase in the photovoltaic efficiency when compared to a randomly oriented nanorod film. [119] However, the insufficient surface area of nanowire/ nanorod arrays seems to be the primary factor that limits the amount of dye adsorption as well as the conversion efficiency of the cells. Many attempts have been made to solve this problem.…”

Effect of water content on growth and optical properties of ZnO nanoparticles generated in binary solvent mixtures by micro-continuous flow synthesis

“…During the past few years, nanocrystals of zinc oxide have attracted a lot of interest due to their potential applications, such as solar cells [1][2][3], photocatalysts [4,5], luminescent materials [6,7], gas sensors [8][9][10] and so on. Different technologies have been developed to synthesize ZnO nanocrystals with different shapes and sizes, including hydrothermal synthesis [11,12], sol-gel method [13][14][15], thermal decomposition [16,17], microwave irradiation method [18][19][20], chemical vapor deposition [21,22], and continuous flow techniques [23,24].…”

The effect of cooling rate during hydrothermal synthesis of ZnO nanorods

“…The increasing interest in nanoscale structures can be attributed to their unique optical and electrical properties due to quantum confinement effects and high surface-to-volume ratios, with great prospect of applying them as building blocks in electronic and photonic devices [2][3][4][5]. The methods reported for the synthesis of semiconducting oxide nanowires include chemical bath deposition [5][6][7][8], hydrothermal synthesis [9][10][11][12][13], chemical vapor deposition [14,15], thermal evaporation [16,17] and sputtering [18,19]. Hydrothermal synthesis is often used because it allows control of size, morphology and crystallinity by tuning of the experimental variables.…”