One-step fabrication of ultrathin layered 1T@2H phase MoS2 with high catalytic activity based counter electrode for photovoltaic devices

The metallic phase of molybdenum disulfide (M-MoS2) and semiconductor phase of molybdenum disulfide (S-MoS2) was synthesized by hydrothermal method, using cetyltrimethylammonium bromide (CTAB) as a surfactant. The structural and elemental composition confirmed the formation of M-MoS2 and S-MoS2. From the morphological analysis layered nanosheets with an inter-layered distance of 0.62 nm for M-MoS2 and 0.95 nm for S-MoS2 was observed. Fourier-transform infrared (FT-IR) spectral analysis was used to investigate the existence of CTAB functional group. The peak at 885 cm−1 attributed to the CH3 bond which confirmed the presence of CTAB in the S-MoS2. The anodic and cathodic peak separation (Epp) values of the counter electrode (CE) has showed at 468.28 mV (M-MoS2) and 540.87 mV (S-MoS2). The M-MoS2 thin film shows higher catalytic activity when compared to S-MoS2 due to more active sites and electronic conductivity. The power conversion efficiency of M-MoS2 CE based device exhibits higher efficiency compared to S-MoS2 CE based device.