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Molecular-scale modulation of interfaces between different unilamellar nanosheets in superlattices is promising for efficient catalytic activities. Here, three kinds of superlattices from alternate restacking of any two of the three unilamellar nanosheets of MoS 2 , NiFe-layered double hydroxide (NiFe-LDH), and graphene are systematically investigated for electrocatalytic water splitting. The MoS 2 /NiFe-LDH superlattice exhibits a low overpotential of 210 and 110 mV at 10 mA cm −2 for oxygen evolution reaction (OER) and alkaline hydrogen evolution reaction (HER), respectively, superior than MoS 2 / graphene and NiFe-LDH/graphene superlattices. High activity and stability toward the overall water splitting are also demonstrated on the MoS 2 /NiFe-LDH superlattice bifunctional electrocatalyst, outperforming the commercial Pt/C-RuO 2 couple. This outstanding performance can be attributed to optimal adsorption energies of both HER and OER intermediates on the MoS 2 /NiFe-LDH superlattice, which originates from a strong electronic coupling effect at the heterointerfaces. These results herald the interface modulation of superlattices providing a promising approach for designing advanced electrocatalysts.

2D materials are regarded as promising electrode materials for rechargeable batteries because of their advantages in providing ample active sites and improving electrochemical reaction kinetics. However, it remains a great challenge for 2D materials to fulfill all requirements for high‐performance energy storage devices in terms of electronic conductivity, the number of accessible active sites, structural stability, and mass production capability. Recent advances in constructing 2D material‐based heterostructures offer opportunities for utilizing synergistic effects between the individual blocks to achieve optimized properties and enhanced performance. In this perspective, the latest advances of 2D material‐based heterostructures are summarized, with particular emphasis on their multifunctional roles in high‐performance rechargeable batteries. Synthetic strategies, structural features in mixed dimensionalities, structure engineering strategies, and distinct functionalities of the 2D material‐based heterostructures in various electrochemical applications are systematically introduced. Finally, challenges and perspectives are presented to highlight future opportunities for developing 2D material‐based heterostructures for practical energy storage.

Accumulating evidence shows that elevated levels of reactive oxygen species (ROS) are associated with cancer initiation, growth, and response to therapies. As concentrations increase, ROS influence cancer development in a paradoxical way, either triggering tumorigenesis and supporting the proliferation of cancer cells at moderate levels of ROS or causing cancer cell death at high levels of ROS. Thus, ROS can be considered an attractive target for therapy of cancer and two apparently contradictory but virtually complementary therapeutic strategies for the regulation of ROS to treat cancer. Despite tremendous resources being invested in prevention and treatment for cancer, cancer remains a leading cause of human deaths and brings a heavy burden to humans worldwide. Chemotherapy remains the key treatment for cancer therapy, but it produces harmful side effects. Meanwhile, the process of de novo development of new anticancer drugs generally needs increasing cost, long development cycle, and high risk of failure. The use of ROS-based repurposed drugs may be one of the promising ways to overcome current cancer treatment challenges. In this review, we briefly introduce the source and regulation of ROS and then focus on the status of repurposed drugs based on ROS regulation for cancer therapy and propose the challenges and direction of ROS-mediated cancer treatment.

Superconducting quantum interference device (SQUID) has extremely high magnetic field sensitivity, current sensitivity, and can detect a low-noise weak current signal. The SQUID current sensor has become the only option of the readout of low-noise detector, such as transition-edge sensor (TES). In this paper, a second-order gradiometric cross-coupled SQUID current sensor for TES application is developed. According to the requirements for TES detectors, the structure and various parameters of SQUID current sensor are designed. The SQUID loop, input coil and feedback coil of the SQUID current sensor all use the second-order gradiometric structure. All the couple ways between SQUID loop and input coil or feedback coil adopt cross-coupling mode in different planes, which can effectively weaken the parasitic capacitance. A second-order gradiometric cross-coupled SQUID current sensor based on Nb/Al-AlO<i>_x</i>/Nb Josephson junction is successfully fabricated on a silicon wafer by optimizing the process. The properties of the second-order gradiometric cross-coupled SQUID current sensor are measured at liquid helium temperature. The bias current of SQUID is 215 μA when the modulation depth of <i>V</i>-<i>Φ</i> modulation curve is maximum. The maximum modulation peak of SQUID is 31 μV. The flux-to-voltage transfer coefficient of SQUID is 108 μV/<i>Φ</i>₀. The input coil current sensitivity is 17 μA/<i>Φ</i>₀, the mutual inductance between SQUID loop and input coil is 117 pH. The current sensitivity of feedback coil is 86 μA/<i>Φ</i>₀, the mutual inductance between SQUID loop and feedback coil is 23 pH. The second-order gradiometric cross-coupled SQUID current sensor has a white flux noise of 2 μ<i>Φ</i>₀/<inline-formula><tex-math id="M3">\begin{document}$ \sqrt{{\rm{H}}{\rm{z}}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20201816_M3.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20201816_M3.png"/></alternatives></inline-formula> and a white current noise of 34 pA/<inline-formula><tex-math id="M4">\begin{document}$ \sqrt{{\rm{H}}{\rm{z}}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20201816_M4.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20201816_M4.png"/></alternatives></inline-formula> with 1/<i>f</i> corner frequency around 200 Hz. The result of noise level under the condition without magnetic shielding shows that the SQUID current sensor with second-order gradiometric cross-coupled structure has an excellent capability of weakening the environmental electromagnetic interference. In the future, we will further improve the mutual inductance of the second-order gradiometric cross-coupled SQUID current sensor between SQUID loop and input coil, optimize the size and critical current of Josephson junction, in order to improve the input sensitivity of SQUID device, reduce the current noise level and the 1/<i>f</i> corner frequency, and meet more requirements for TES applications.

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