No abstract

FeS2/carbon tightly anchored on carbon cloth was developed as a counter electrode for dye-sensitized solar cells with efficiency and stability exceeding those of Pt.

Room‐temperature, high‐sensitivity, and broadband photodetection up to the shortwave infrared (SWIR) region is extremely significant for a wide variety of optoelectronic applications, including contamination identification, thermal imaging, night vision, agricultural inspection, and atmospheric remote sensing. Small‐bandgap semiconductor‐based SWIR photodetectors generally require deep cooling to suppress thermally generated charge carriers to achieve increased sensitivity. Meanwhile, the photogating effect can provide an alternative way to achieve superior photosensitivity without the need for cooling. The optical photogating effect originates from charge trapping of photoinduced carriers at defects or interfaces, resulting in an extremely high photogain (106 or higher). Here, a highly sensitive SWIR hybrid photodetector, fabricated by integrating an organic charge transfer complex on a graphene transistor, is reported. The organic charge transfer complex (tetrathiafulvalene–chloranil) has an exceptional low‐energy intermolecular electronic transition down to 0.5 eV, with the aim of achieving efficient SWIR absorption for wavelengths greater than 2 µm. The photogating effect at the organic complex and graphene interface enables an extremely high photogain and a high detectivity of ≈1013 Jones, along with a response time of 8 ms, at room temperature for a wavelength of 2 µm.

Three-terminal synaptic transistors are basic units of neuromorphic computing chips, which may overcome the bottleneck of conventional von Neumann computing. So far, most of the three-terminal synaptic transistors use the dielectric layer to change the state of the channel and mimic the synaptic behavior. For this purpose, special dielectric layers are needed, such as ionic liquids, solid electrolytes, or ferroelectric insulators, which are difficult for miniaturization and integration. Here, we report a novel type of synaptic transistors using a two-dimensional ferroelectric semiconductor, i.e., α-In2Se3, as the channel material to mimic the synaptic behavior for the first time. The essential synaptic behaviors, such as single-spike response, paired-spike response, and multispike response have been experimentally demonstrated. Most importantly, the conventional gate dielectric material of our transistors may facilitate the miniaturization and batch manufacture of synaptic transistors. The results indicate that the three-terminal synaptic transistors based on two-dimensional ferroelectric semiconductors are very promising for neuromorphic systems.