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Two‐dimensional transition metal dichalcogenides (2D TMDs) are promising as sensing materials for flexible electronics and wearable systems in artificial intelligence, tele‐medicine, and internet of things (IoT). Currently, the study of 2D TMDs‐based flexible strain sensors mainly focuses on improving the performance of sensitivity, response, detection resolution, cyclic stability, and so on. There are few reports on power consumption despite that it is of significant importance for wearable electronic systems. It is still challenging to effectively reduce the power consumption for prolonging the endurance of electronic systems. Herein, we propose a novel approach to realize ultra‐low power consumption strain sensors by reducing the contact resistance between metal electrodes and 2D MoS2. A dendritic bilayer MoS2 has been designed and synthesized by a modified CVD method. Large‐area edge contact has been introduced in the dendritic MoS2, resulting in decreased the contact resistance significantly. The contact resistance can be down to 5.4 kΩ μm, which is two orders of magnitude lower than the conventional MoS2 devices. We fabricate a flexible strain sensor, exhibiting superior sensitivity in detecting strains with high resolution (0.04%) and an ultra‐low power consumption (33.0 pW). This study paves the way for future wearable and flexible sensing electronics with high sensitivity and ultra‐low power consumption. [ABSTRACT FROM AUTHOR]

Twisted bilayer (TB) transition metal dichalcogenides (TMDCs) beyond TB-graphene are considered an ideal platform for investigating condensed matter physics, due to the moiré superlattices-related peculiar band structures and distinct electronic properties. The growth of large-area and high-quality TB-TMDCs with wide twist angles would be significant for exploring twist angle-dependent physics and applications, but remains challenging to implement. Here, we propose a reconfiguring nucleation chemical vapor deposition (CVD) strategy for directly synthesizing TB-MoS2 with twist angles from 0° to 120°. The twist angles-dependent Moiré periodicity can be clearly observed, and the interlayer coupling shows a strong relationship to the twist angles. Moreover, the yield of TB-MoS2 in bilayer MoS2 and density of TB-MoS2 are significantly improved to 17.2% and 28.9 pieces/mm2 by tailoring gas flow rate and molar ratio of NaCl to MoO3. The proposed reconfiguring nucleation approach opens an avenue for the precise growth of TB-TMDCs for both fundamental research and practical applications. Twisted bilayers of 2D semiconductors are being intensively investigated due to their emergent physical properties, but their controlled bottom-up synthesis remains challenging. Here, the authors report a confined-space chemical vapour deposition strategy to synthesize MoS2 bilayers with twist angles ranging from 0° to 120°. [ABSTRACT FROM AUTHOR]

Heterostructure construction and doping provide two powerful routes for manipulating charge carrier separation, electrical transport, optical response, and interface kinetics for photocatalysis. However, the literature reported synthetic methods until now were very time-consuming. In this work, a facile one-pot hydrothermal reaction route was designed to synthesize Si nanospheres @ Ti 3 + self-doped TiO2 nanosheet heterostructure with tunable Ti 3 + doping levels at different hydrothermal temperatures. It was found that the precursor Si nanospheres not only serve as supporter of TiO2 nanosheets, but also are the inducement of Ti 3 + doping. Due to the synergistic effect of Ti 3 + doping and Si/TiO2 heterojunctions, the optimal sample exhibited 6.74-fold enhancement for rhodamine B (RhB) photodegradation under Xe lamp irradiation compared with the pristine TiO2. The construction of Si/TiO2 heterojunction, as well as the introduced Ti 3 + doping and associated oxygen vacancies, extended the optical absorption of TiO2 into visible region and enhanced the separation efficiency of photogenerated electron-hole pairs, which finally resulted in improved photocatalytic performance of the Si@Ti 3 + self-doped TiO2 core–shell nanospheres. The designed hydrothermal route opens up an opportunity to the synthesis of doped hetero-photocatalysts in an efficient way. In the current study, Si nanospheres @Ti3+ self-doped TiO2 nanosheet heterostructure with tunable Ti3+ doping levels has been successfully fabricated by a facile one-pot hydrothermal method. The synergistic effect of Ti3+ doping and Si/TiO2 heterojunctions extends the optical absorption of TiO2 into the visible region and enhances the separation efficiency of photogenerated electron–hole pairs. The as-synthesized Si@Ti3+-TiO2 samples display higher photoactivity for organic pollutants degradation compared with pristine TiO2. [ABSTRACT FROM AUTHOR]

The introduction of rotational freedom by twist angles in twisted bilayer (TB) transition metal dichalcogenides (TMDCs) can tailor the inherent properties of the TMDCs, which provides a promising platform to investigate the exotic physical properties. However, direct synthesis of high-quality TB-TMDCs with full twist angles is significantly challenging due to the substantial energy barriers during crystal growth. Here, a modified chemical vapor deposition strategy is proposed to synthesize TB-WS 2 with a wide twist angle range from 0° to 120°. Utilizing a tilted SiO 2 /Si substrate, a gas flow disturbance is generated in the furnace tube to create a heterogeneous concentration gradient of the metal precursor, which provides an extra driving force for the growth of TB-WS 2 . The Raman and photoluminescence results confirm a weak interlayer coupling of the TB-WS 2 . High-quality periodic Moiré patterns are observed in the scanning transmission electron microscopy images. Moreover, owing to the strong correlation between the nonlinear optical response and the twisted crystal structure, tunable second harmonic generation behaviors are realized in the TB-WS 2 . This approach opens up a new avenue for the direct growth of high-crystalline-quality and pristine TB-TMDCs and their potential applications in nonlinear optical devices., (© 2024 Wiley‐VCH GmbH.)