Demonstration of hybrid bulk heterojunction (BHJ) solar photovoltaic cell employing molybdenum disulfide (MoS2)/titanium dioxide (TiO2) nanocomposite (∼15 μm thick) and poly 3-hexylthiophene (P3HT) active layers is presented in this letter. The dominant Raman peak at 146 cm−1 confirmed TiO2, while two other peaks observed at 383 cm−1 and 407 cm−1 asserted MoS2 in the nanocomposite film. The demonstrated BHJ solar cell, having a stacked structure of indium tin oxide/TiO2/MoS2/P3HT/gold, exhibits a short circuit current density of 4.7 mA/cm2, open circuit voltage of 560 mV, and photoconversion efficiency of 1.3% under standard AM1.5 illumination condition. We observe that the quality of TiO2/MoS2/P3HT interfaces, as reflected in the dark saturation current in low- and medium-forward-bias region, plays a key role in impacting solar cell performance due to interfacial recombination effect.

Hysteretic switching in the magnetoresistance of short-channel, ferromagnetically contacted individual single wall carbon nanotubes is observed, providing strong evidence for nanotube spin transport. By varying the voltage on a capacitively coupled gate, the magnetoresistance can be reproducibly modified between +10% and -15%. The results are explained in terms of wave vector matching of the spin polarized electron states at the ferromagnetic / nanotube interfaces.

We demonstrated Schottky-barrier solar cell using layer-structured semiconductor tungsten disulfide (WS2) nanofilm (NF) as the photo-active material. WS2 NFs were synthesized by chemical-vapor-deposition initiated on the surface of tungsten. The growth of WS2 NF was confirmed by Raman signature peaks representing active modes of E12g (351.5 cm−1) for in-plane and A1g (420.1 cm−1) for out-of-plane atomic vibrations, respectively. The ITO/WS2/Au Schottky-barrier solar cell was demonstrated by a layer-enabled assembling process, showing a photo-conversion efficiency of 1.7% and effective photon absorption in the wavelength range of 350 nm–950 nm. The Mott-Schottky characteristic suggests low density of bulk and interface defects in WS2 NF attributed to surfaces with negligible amount of dangling bonds which is the essential nature of layered semiconductors.