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Two-dimensional layered transition metal dichalcogenides (TMDs) have been widely employed as functional materials in promising electronics and optoelectronic devices due to their unique physical and outstanding electronic properties. However, 2D MoS2 as a representative TMDs semiconductor with a low light absorption ability and narrow spectra absorption range will extremely restrict their potential application for high-performance optoelectronics. To overcome this issue, 2D TDMs based heterostructure photodetectors have been successfully demonstrated in this work by integrating a one-step synthesis of air stability of semiconductor PbSe nanocrystal inks with 2D MoS2. The PbSe/2D MoS2 heterostructure photodetector exhibits a light-to-dark current ratio of ∼102, a high responsivity of 23.5 A W−1, a detectivity of 3.17 × 1010 Jones, and stability in ambient conditions as well. Compared with the pristine 2D MoS2 photodetector, the responsivity and detectivity of the PbSe/MoS2 photodetector are improved by 512% and 483%, respectively. More importantly, the photoresponse of the PbSe/MoS2 heterostructure photodetector can extend to the near-infrared (NIR) light region while still maintaining the responsivity and detectivity of 19.7 A W−1 and 2.65 × 1010 Jones, respectively, under 808 nm light illumination. The reasons for the excellent performance of the PbSe/MoS2 heterostructure photodetector have also been studied and discussed in detail in this work, which will shed light on constructing high-performance NCs/2D TMDs heterostructure optoelectronics. [ABSTRACT FROM AUTHOR]

In this study, we investigate the structure and optical, electrical and magnetic properties of Mn-doped Bi5Ti3FeO15 (BTFO) thin films. While Mn-doping does not almost change the structure and unit cell volume of BTFO, lattice distortion occurs and the optical bandgap is significantly reduced. More importantly, the ferroelectric and ferromagnetic properties are correspondingly improved after doping. However, a high concentration of doped-Mn largely increases the leakage due to the excessive introduction of oxygen vacancy, which is intrinsically benefitial to the ferromagnetic property. This makes Mn-doped BTFO have a great research value and application prospects, including the photovoltaic effect of ferroelectric and ferroelectric–ferromagnetic storages. [ABSTRACT FROM AUTHOR]

Perovskites have attracted intensive attention as promising materials for the application in various optoelectronic devices due to their large light absorption coefficient, high carrier mobility, and long charge carrier diffusion length. However, the performance of the pure perovskite nanocrystals-based device is extremely restricted by the limited charge transport capability due to the existence of a large number of the grain boundary between perovskite nanocrystals. To address these issues, a high-performance photodetector based on all-inorganic CsPbBr3 perovskite nanocrystals/2D non-layered cadmium sulfide selenide heterostructure has been demonstrated through energy band engineering with designed typed-II heterostructure. The photodetector exhibits an ultra-high light-to-dark current ratio of 1.36 × 105, a high responsivity of 2.89 × 102 A W-1, a large detectivity of 1.28 × 1014 Jones, and the response/recovery time of 0.53s/0.62 s. The enhancement of the optoelectronic performance of the heterostructure photodetector is mainly attributed to the efficient charge carrier transfer ability between the all-inorganic CsPbBr3 perovskites and 2D cadmium sulfide selenide resulting from energy band alignment engineering. The charge carriers' transfer dynamics and the mechanism of the CsPbBr3 perovskites/2D non-layered nanosheets interfaces have also been studied by state-state PL spectra, fluorescence lifetime imaging microscopy, time-resolved photoluminescence spectroscopy, and Kelvin probe force microscopy measurements. [ABSTRACT FROM AUTHOR]

Exploiting highly efficient, noble metal-free, and ultra-small H2-evolution cocatalysts is crucial to promoting the photocatalytic water splitting reaction. Herein, ultra-small non-crystalline CuxP nanodots (CuxP-ND) as an efficient H2-evolution cocatalyst were coupled on the TiO2 surface via a simple triethanolamine (TEOA)-assisted photodeposition strategy. Owing to the initially uniform anchoring of the Cu(TEOA)2+ precursor on the TiO2 surface, the final CuxP nanodots show a very small size of 2–5 nm and are homogeneously distributed on the surface of the photocatalyst. The obtained CuxP-ND/TiO2 photocatalysts displayed a significantly enhanced ultraviolet-light H2-production activity and the CuxP-ND/TiO2(1 wt%) sample displayed a maximum hydrogen-production rate of 93.5 μmol h−1 with an apparent quantum efficiency of 7.7%, which is a 30-fold increase compared to bare TiO2. The boosted hydrogen generation can be ascribed to the fact that the ultra-small non-crystalline CuxP nanodots can not only induce the formation of a built-in electric field to improve the rapid transfer of photogenerated electrons, but also provide interfacial hydrogen-production sites to dramatically enhance the H2-generation rate. These new non-crystalline CuxP nanodots with a green and facile preparation procedure can pave a new way to exploit efficient co-catalysts for photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]