QD/MOF nanocomposites as novel photoanode for photocatalytic and photovoltaic applications

Abstract

The article demonstrates quantum dots (QDs) that absorb a wider spectrum of solar light and have been applied for photocatalysis and photovoltaics. Despite several advancements in the field, an opportunity still exists to improve the efficiency of QD-based photocatalysts for hydrogen production and photovoltaic systems. To improve the QD-based photocatalysts and photovoltaic systems, we introduce a novel nanocomposite of PbS QDs with NTU-9 MOFs for improved absorbance of the solar spectrum along with lower recombination losses. PbS/NTU-9 composite shows a visible light-driven photocatalysis of Rhodamine 6G (Rh 6G), resulting in rapid (25 min) and quantitative (>95%) photodegradation of Rh 6G, indicative of the efficient light-assisted charge transfer process in the composite. Additionally, the composite demonstrates significant potential for hydrogen evolution under visible light, at 432.21 μmol cm⁻2, showcasing its versatility in photocatalytic applications. Hydrogen evolution is crucial for sustainable energy solutions as it produces clean fuel from water, aligning with global efforts to reduce carbon emissions and dependency on fossil fuels. The global status of hydrogen as a clean energy carrier is gaining momentum, with increasing investments and research focused on improving its production efficiency and scalability. Further, the PbS/NTU-9 composite was employed as a photoanode material showing ∼40% enhancement in the overall efficiency of a quantum dot sensitized solar cell (QDSSC). The enhancement has been observed mainly in the improvement in short-circuit current and fill factor of the device due to the less recombination and efficient charge transport of photo carriers. We find that PbS/NTU-9 composite has the potential for future highly efficient photovoltaic cells due to benefits of widened absorption region, efficient charge transport, channelized structure, and environmental stability.