Structural, Optical, Photoelectrochemical, and Electronic Properties of the Photocathode CuS and the Efficient CuS/CdS Heterojunction

We report a facile synthesis of CuS and CdS nanoparticles using a cheap solution-processed chemical bath method forming heterogeneous nucleation. The optical, structural, photoelectrochemical (PEC), and electronic properties are studied by implementing relevant experimental techniques. The estimated optical band gap of & SIM;2.10 eV of CuS designates potential application in inexpensive photocatalysis and solar cells. Further, the valence band and conduction band positions of CuS and CdS are evaluated using cyclic voltammetry curves. Narrow conduction and valence band offset potentials measured at the CuS/CdS heterojunction are encouraging factors for the PEC application. The electronic properties are supported by the current density vs potential plots (J-V) with an improved short-circuit current density of 0.71 mA cm-2 for the heterojunction compared to bare CuS showing 0.15 mu A cm(-2). The determined PCE of the heterojunction CuS/CdS is 0.65%.

Automated summary

We report a facile synthesis of CuS and CdS nanoparticles using a cheap solution-processed chemical bath method forming heterogeneous nucleation. The optical band gap of CuS is estimated to be 2.10 eV, indicating its potential application in inexpensive photocatalysis and solar cells. The valence band and conduction band positions of CuS and CdS are evaluated using cyclic voltammetry curves. The narrow conduction and valence band offset potentials measured at the CuS/CdS heterojunction are encouraging factors for the photoelectrochemical (PEC) application. The current density vs potential plots (J-V) support the improved short-circuit current density and determined power conversion efficiency (PCE) of the CuS/CdS heterojunction.