Dye functionalisation of PAMAM-type dendrons grown from vertically aligned single-walled carbon nanotube arrays for light harvesting antennae

Abstract

Vertically aligned single-walled carbon nanotube arrays have shown great promise for applications as electrochemical devices due to their high conductivity and large electrode surface area. There has also been research showing that they can be applied to transparent photovoltaic devices. In this work we synthesised vertically aligned single-walled carbon nanotube arrays and further modified these with PAMAM-type dendrons. These dendrons have previously been shown to increase the photovoltaic performance of the nanotube arrays. The dendrons were then further modified using a ruthenium based dye, commonly known as N3. The presence of this dye on increasing generations of dendron was investigated using electrochemistry to determine the surface concentration and electron transfer co-efficient, with the dye modified generation 1.5 dendron providing the highest surface N3 concentration with 1.98 × 10¹³ molecules cm⁻². Additionally, photovoltaic testing was performed on each generation and the optimal dye modification was found to provide a 35% increase in power output after the dendron functionalisation whilst still using very little material and remaining transparent.