Franckeite-derived van der Waals heterostructure with highly efficient photocatalytic NOx abatement: Theoretical insights and experimental evidences

Addressing the pressing issue of nitrogen oxides (NOx) pollution requires the identification and optimization of efficient materials for NOx removal. This study rigorously explores franckeite, a naturally occurring van-derWaals heterostructure, for its photocatalytic potential in NOx elimination. Employing ab-initio calculations underpinned by density functional theory (DFT) and the many-body BerkeleyGW (GW) plus Bethe-Salpeter (GWBSE) approach, we analyze franckeite's structural, electronic, and optical characteristics, including its absorption spectra. Our experimental data indicate a substantial improvement in NO removal efficiency, ranging from 30% to a remarkable 100% under specific conditions. We find a direct correlation between removal efficiency and gas flow rate; higher rates reduce catalyst-NO interaction time. Additionally, we identify radical species responsible for oxidizing NO to nitrates/nitrites. Franckeite demonstrated both stability and reusability, achieving an average efficiency of 95% during three continuous hours of testing. These findings open new avenues for scaling up the use of Franckeite in environmental applications.