Ag2S/CdS-Heterostructured Nanorod Synthesis by L-Cysteine-Mediated Reverse Microemulsion Method

Highly-efficient charge separation is of significant importance for the improvement of photocatalytic performance towards solar H-2 production. Here, Ag2S/CdS hetero nanorods with intimate contact were fabricated at ambient temperature by L-cysteine-assisted method involving a Triton X-100/cyclohexane/hexanol/water quaternary W/O reverse microemulsion process. The formation of Ag2S/CdS nanojunction is verified by XRD, TEM, HRTEM, EDS as well as XPS technique, while the photocatalytic activity of Ag2S/CdS hetero nanorod is assessed by water photo-reduction to H-2 in the presence of S2-/SO32- as sacrificial agents under visible-light irradiation. It is demonstrated that Ag2S/CdS hetero nanorod exhibits an about 480-fold enhancement in the H-2-evolution rate relative to that of pristine CdS. In combination with UV-vis absorption and photoluminescence spectra, the synergistic effects stemmed from the extended light-absorption and facilitated charge-separation between the interfaces largely contribute to boosting the photocatalytic H-2-evolution activity of CdS nanorod. This work offers a novel strategy to in-situ construct CdS-based heterostructured photocatalysts with good performance and low cost.