Introduction of phosphorus-doped CeO2 decorated with MoSe2 nanosheets anchored on nitrogen-doped carbon nanotubes for accelerating the triiodide reduction in dye-sensitized solar cells

Designing of inexpensive and robust counter electrode (CE) material without noble metals is of great essential for improving the overall power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). Herein, we successfully prepared the phosphorus-doped CeO2@MoSe2 anchored on nitrogen-doped carbon nanotubes (P-CeO2@MoSe2/N-CNTs) via a hydrothermal strategy, and consequent phosphorization-sonication process and used as CE for DSSC. Based on the electrochemical studies, the P-CeO2@MoSe2/N-CNTs CE displayed remarkable catalytic activities, great electron transfer ability, and high stability in the I3−/I− electrolyte. More importantly, the device equipped with P-CeO2@MoSe2/N-CNTs CE yielded an outstanding PCE of 8.32 %, surpassing that of standard platinum (PCE = 6.75 %) and other corresponding counterparts. Such notable photovoltaic performance can be ascribed to (i) the positively synergistic coupling effect of P doping into CeO2, (ii) the synergistic effect between P-CeO2 nanorods and MoSe2 nanosheets, (iii) and support role of conductive carbon network, which offer abundant catalytic active sites, and exceptional electrical conductivity. The computations indicated that the HOMO-LUMO bandgap of P-CeO2@MoSe2/N-CNTs was lower than other CEs which confirms that the electron transfer has been facilitated by anchoring of P-CeO2@MoSe2 on N-CNTs. [Display omitted] •The P-CeO2@MoSe2/N-CNTs prepared via the hydrothermal and consequent phosphorization-sonication process.•The efficiency of dye-sensitized solar cells based on P-CeO2@MoSe2/N-CNTs counter electrode reached 8.32 %.•The P-CeO2@MoSe2/N-CNTs as CE exhibited superior electrochemical stability and activity.•The P-CeO2@MoSe2/N-CNTs electrocatalyst can be considered as a counter electrode for dye-sensitized solar cells.