The twist-angle dependence of exciton absorption in a molybdenum disulfide (MoS2)/graphene heterostructure (MGH) is reported. Using photoluminescence (PL) spectroscopy, we found that, as the twist angle increased, the MGH demonstrated an enhancement of PL intensity and a peak position blueshift, indicating that the exciton radiative recombination was positively correlated with the twist angle. In addition, optical reflectance measurements were performed in order to investigate the exciton absorption in the MGH. It was found that the reflectance of MGH samples was twist-angle dependent at wavelengths of 620 and 670 nm, which corresponds to the PL peak positions of MoS2. This was attributed to the change in interlayer charge transfer for different twist angles. Our findings confirm the tunability of the electronic structure in MGHs via the interlayer twist, which enriches our understanding of interlayer coupling and is important for the future development of electronic and optoelectronic devices based on 2D material heterostructures.

A method to grow few-layer graphene in the form of an “inverted pagoda” is proposed by controlling the pressure and the flow rate in a circulating chemical vapor deposition system.

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A series of donor (D)−acceptor (A)-conjugated monomers (ECzE-NB and ECzE-AQ) were designed and synthesized by EDOT-carbazole-EDOT (ECzE) acting as a donor (D) and anthraquinone (AQ) and nitrobenzene (NB) acting as acceptors (A) in this study. The corresponding polymer films (PECzE, PECzE-NB, and PECzE-AQ) were obtained by electrochemical polymerization, and then the effects of different acceptors on the structure and electrochemical performance of the polymers were studied. Through NMR, mass spectrometry (MS), and Fourier transform infrared spectroscopy (FT-IR), it was proved that the monomers were successfully synthesized. The results of the electrochemical performance test illustrated that the electrochemical behavior of PECzE was a typical nondiffusioncontrolled process. When the current density was 0.1 mA/cm 2 , the specific capacity of PECzE was 8.41 mF/cm 2 with a rather good rate performance. However, the electrochemical behaviors of PECzE-NB and PECzE-AQ were different from that of PECzE owing to the ability of hole injection and spatial structures of the monomers changed by introducing electron-withdrawing groups.

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