# Photodegradation of mixed organic dyes using Nb and W co-doped spray coated transparent conducting SnO2 thin films

## TL;DR

Scientists developed a transparent conducting material that efficiently degrades mixed dyes using light, offering a sustainable and stable photocatalytic solution.

## Contribution

The study introduces Nb and W co-doped SnO2 thin films as a novel transparent conducting electrode for sustainable dye degradation.

## Key findings

- Nb and W co-doping reduces contact angle and alters SnO2 thin film surface features.
- The co-doped films show low sheet resistance and high photocatalytic activity for mixed dye degradation.
- Defect-mediated photocatalysis using LED light and immobilized thin films provides cycling stability.

## Abstract

The implications of niobium (Nb) and tungsten (W) co-dopants on the physicochemical characteristics of spray deposited tin oxide (SnO2) thin films are investigated in order to evaluate it as an alternative transparent conducting oxide electrode. Co-doping with two cationic elements enables tweaking of the morphological and optoelectronic properties of SnO2 in thin film form. Spray pyrolysis is utilized for obtaining Nb (1 and 2 wt%) and W (fixed 4 wt%) co-doped SnO2 thin films on glass substrates. The surface wettability test shows that the cationic co-dopants W and Nb have influenced the SnO2 thin film by altering the surface features thereby reducing the contact angle value. The transmittance spectra indicate that pure SnO2 has a higher transmittance value of 83%, which diminishes upon addition of the W dopant and increases after Nb is introduced as a co-dopant. The linear four-probe measurement revealed that the films have a uniform sheet resistance around the centre with a low sheet resistance of ∼62 Ω □−1. The stabilized transparent conducting electrode's figures of merit of the deposited W and Nb co-doped SnO2 thin films are calculated and the promising results of photocatalytic tests for mixed dyes are discussed in correlation with the physicochemical and optoelectronic properties.

A potential strategy is devised to promote defect-mediated photocatalysis using LED light and immobilised spray-coated Nb and W codoped SnO2 thin-film photoelectrodes to degrade mixed dyes sustainably and with significant cycling stability.