High performance photodetectors based on van der Waals heterostructures (vdWHs) are crucial to developing micro-nano-optoelectronic devices. However, reports show that it is difficult to balance fast response and high sensitivity. In this work, we design a photovoltaic field-effect photodiode (PVFED) based on the WSe2/MoS2/WSe2 double vdWHs, where the photovoltage that originated from one vdWH modulates the optoelectronic characteristics of another vdWH. The proposed photodiode exhibits an excellent self-powered ability with a high responsivity of 715 mA·W–1 and fast response time of 45 μs. This work demonstrates an efficient method that optimizes the photoelectric performance of vdWH by introducing the photovoltaic field effect.

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Metal phosphorus trichalcogenides (MPX3) have attracted extensive attention as promising two-dimensional (2D) layered materials in future electronic and optoelectronic devices. Here, few-layer In4/3P2Se6 nanoflakes have been successfully exfoliated, for the...

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Engineering of TiO photoanode is an important strategy for increasing the photovoltaic conversion efficiency of quantum dots-sensitized solar cells (QDSSCs). In this work, three-dimensional ordered macroporous (3DOM) TiO films are fabricated by the controlled infiltrating-calcination method using the close-packed polystyrene spheres colloidal crystals as templates. The as-prepared macroporous TiO films are then applied as the photoanode in colloidal CdSe QDSSCs. This structure not only facilitates the penetration of thioglycolic acid capped CdSe QDs, and thus achieving a high coverage of the internal surface with QDs sensitizer, but also exhibits a photonic band gap with tunable positions, which could enhance the light absorption. As a result, the liquid-junction QDSSCs assembled with the CdSe sensitized 3DOM TiO yields a power conversion efficiency of 3.60% under solar illumination of 100 mW cm, and this value is much higher than that of the device using nanoporous TiO photoanode (1.82%). Our results indicate that the 3DOM TiO is a promising candidate for the construction of high-efficiency QDSSCs.