Rational Design of Zero-Dimensional Gold Cluster/Two-Dimensional TMD Heterostructures for Enhanced Photocatalytic and Optoelectronic Performance

In optoelectronic conversion technologies and photocatalytic applications, single-component materials often face limitations such as low carrier separation efficiency and restricted bandgap tunability. To overcome the limitations of single-component materials in optoelectronics and photocatalysis, we constructed 0D/2D van der Waals heterostructures (vdWHs) by loading gold clusters (Aun, n = 4, 10, and 20) onto monolayer transition metal dichalcogenides (TMDs). Notably, the Au20/MoS2 vdWH exhibits Z-scheme charge transfer behavior, which promotes efficient electron–hole separation while retaining a high redox potential, thereby significantly improving its photoelectrochemical performance. Furthermore, a comparative analysis of the formation mechanisms and UV–visible absorption spectra of the Z-scheme Au20/MoS2 and conventional type-II Au20/WTe2 vdWHs reveals that Au20 loading markedly improves the light absorption capabilities of the TMD monolayers, increasing absorption by 33.62% and 18.01%, respectively. This work offers a design strategy for high-performance optoelectronic devices and demonstrates that tuning vdWH types enhances their efficiency in applications.