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In this review, we summarize several important BP-based nanohybrids and the majority of the reported synthetic routes, properties as well as applications of the nanohybrids.

A generic strategy to regulate various synaptic transistors is of great significance for the integration of multiple synaptic devices with multiple neuromorphic functionalities (e.g., olfactory, auditory, visual sensations, etc.) in an artificial neural network. Here, side-liquid-gated n-type In2O3, 2D MoS2, and p-type pentacene synaptic transistors based on a proton conducting mechanism and hysteresis engineering are proposed. The operating voltage can be significantly reduced from 30 to 3 V by using a high permittivity Er2O3 dielectric layer replacing traditional SiO2. Fundamental synaptic behaviors of both short-term plasticity (STP) and long-term plasticity (LTP) are successfully emulated on all three devices, providing the opportunity to integrate different semiconductor materials on one single chip to fabricate a multifunctional brain network. Interestingly, the PEO and PEO:LiClO4 side-gate electrolytes display different inhibitory post-synaptic currents (IPSCs) due to the difference in the proton-conducing activity and this generates distinct dynamic filtering response characteristics. Most importantly, a proof-of-principle artificial stereo vision system for 3D-object recognition is also constructed based on multiterminal In2O3/Er2O3 synaptic transistors. This novel side-gate regulating strategy is expected to accelerate the development of sophisticated neural networks and provide a great potential for neuromorphic applications.

Despite many decades of substantial research on doping technologies, which are critical for 2D materials used in optical and electrical devices, efforts on selective doping of 2D materials are still scarce. Here, a novel band matching doping strategy is introduced in highly selective doping of WSe2. The key to its realization is the use of dopants whose molecular orbitals closely match the band structure of the 2D materials to be doped. By gradually adjusting the exposure time in iodine vapor, the carrier polarity of the WSe2 FET from the n-type to the p-type can be reversely controlled, whereas the carrier type of ReS2, MoS2, MoSe2, MoTe2, and WS2 remains unchanged. The iodine vapor treatment is also utilized in the manufacturing process flow of high-performance p–n homojunctions with a near-unity ideality factor of 1.002 along with a current rectification of ∼104 and a complementary inverter on a single WSe2 nanosheet. Moreover, selective doping allows the WSe2/ReS2 diode to change from n–n to p–n type for the first time and greatly enhances its photodetection capability. This work presents important progress in selective modulation of the electrical properties of a certain material in an integrated multiple 2D material array.

Manipulation of conditions during the electrochemical exfoliation of graphite is in great demand for the large-scale manufacture of high-quality graphene. Here, we developed a new electrolysis system to manufacture high-quality graphene using double-graphite foil as an electrode. We employed alternating currents to the power system. Graphene with sulfur particles on the surface (GSP) was successfully prepared by adding thiourea into the ammonium sulfate electrolyte. CH4N2S acted as a source of sulfur and regulated the radicals (e.g., HO˙). Thus, exfoliation was controlled. The as-prepared GSP (1% CH4N2S) displayed a relatively high electromagnetic interference (EMI) shielding effectiveness (SE) value of 32.46 dB (thickness of 0.208 mm). In the meantime, we study and confirm that the free radicals could also be regulated by lowering the temperature. The as-prepared graphene exhibited an EMI SE value of 21.05 dB (thickness of 0.239 mm), when the temperature of the electrochemical exfoliation was reduced to 20 °C.

We developed a facile method of combustion synthesis followed by a selenylation process to synthesize carbon-encapsulated CdSe hybrid nanobelts. In the nanohybrids, hexagonal-wurtzite-structured CdSe quantum dots (QDs) are formed in situ and embedded uniformly in the carbon nanobelt (CNB) matrix, resulting in the formation of an analogous p–i–n junction along the radius of the QDs due to the appearance of an inversion layer on the QD surfaces, which favors the separation of photoexcited electron–hole pairs by built-in electric field. Electrons accumulate in the QD core, while holes migrate to the QD surface and then quickly transfer to the CNB matrix. Additionally, the nanohybrids can enhance significantly the absorption of the whole energy range of visible light. The nanohybrids can show p-type conductivity with hole mobility as high as 1.4 × 104 cm2 V−1 s−1, and, furthermore, the single nanohybrid-based devices not only show excellent photodetection performance at a certain bias, but also show photovoltaic-based self-powered photodetection performance at zero bias upon illuminating one end electrode of the devices, pointing a way to the development of novel photoelectronic materials and devices for energy applications.

Layered GeSe2 nanobelts doped with Bi have been synthesized by thermal reduction of Bi2Se3 nanopowder using germanium (Ge). The nanobelts prepared showed excellent p-type conductivity, with hole mobility as high as 690 cm2 V−1 s−1. The introduction of Bi leads to the formation of a commensurate superstructure, and induces the growth of nanobelts along the [010] direction. Two-terminal devices, based on individual GeSe2:Bi nanobelts with Ag electrodes, showed symmetrical resistive switching (RS) behavior accompanied by negative differential resistance. A space charge polarization model has been proposed. For the doping of Bi, the ordered superstructure defects and variable valences create trap centers, in which charges can effectively be captured and stored to generate polarization effects under a relatively large applied electric field. Additionally, the relatively large negative RS window can further be utilized as a non-volatile resistance random access memory (RRAM). The superior stability, reversibility, non-destructive readout and good cycling performance of the nanodevices demonstrated that Bi-doped GeSe2 nanobelts have considerable potential in next-generation non-volatile memory applications.