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Two-dimensional MA2Z4, as another system of a two-dimensional material family, can obtain different materials and considerable properties by replacing the elements M, A, and Z. At present, the physical properties and optical response of MA2Z4 materials have been studied, but there is still a lack of research on the application of MA2Z4 as a transistor channel material to investigate its transistor performance. Here, we employ WGe2N4 as a representative to systematically study the bounce-to-transport properties and gate control capability of ML WGe2N4 field effect transistors below 10 nm via ab initio quantum transport calculations. Until the channel length is down to 3.0 nm, the optimized n/p-type doped WGe2N4 metal–oxide–semiconductor field-effect transistors with proper concentrations and underlap structures can satisfy the high-performance requirements of International Technology Roadmap for Semiconductors of 2013 version, by considering the on-current, subthreshold swing, intrinsic delay time, and dynamic power indicator. Therefore, we can estimate that the monolayer WGe2N4 is a competitive alternative for transistor channel materials in the post-silicon era.

The molecular-level interactions of an antimicrobial peptide melittin with supported membrane were studied by the combination of dissipative quartz crystal microbalance (QCM-D) experiments and computer simulations. We found the response behavior of lipids upon peptide adsorption greatly influence their interactions. The perturbance and reorientation of the lipid in liquid phase facilitate the insertion of melittin in a trans-membrane way, but in solid phase, asymmetrical membrane disruption happens. Apart from the lipid state, the local peptide-to-lipid ratio also affects the insertion capacity of melittin. When the local peptide number density is high, adjacent peptides can cooperatively penetrate into the membrane. This observation explains the occurrence of the conventional "carpet" mechanism.

Vertically oriented multilayered MoS2 nanosheets were successfully grown on p-GaN nanorod substrate using chemical vapor deposition (CVD) method. The p-GaN nanorod substrate was fabricated by dry etching employing self-assembled nickel (Ni) nanopartical as mask. Photoluminescence (PL) and Raman characterizations demonstrate the multilayered structure of MoS2 nanosheet growth on p-GaN nanorods as compared with the referential monolayer MoS2 on GaN wafer substrate under the same growth procedure. The growth model of vertical MoS2 nanosheet formed on GaN nanorods is evidently proposed according to the first-principle calculations. More importantly, it is demonstrated here that the as-grown vertical MoS2 nanosheets/p-GaN nanorod heterostructure holds promising applications in photodetector device, where high optical gain and broad spectral response in the visible range have been obtained.

Environmentally responsive materials are attractive for advance biomedicine applications such as controlled drug delivery and gene therapies. Recently, we have introduced the fabrication of a novel type of stimuli-sensitive lipogel composite consisting of poly(N-isopropylacrylamide) (pNIPAM) microgel particles and lipids. In this study, we demonstrated the temperature-triggered drug release behavior and the tunable drug loading and release capacities of the lipogel. At room temperature (22 °C), no calcein was released from the lipogel over time. At body temperature (37 °C), the release process was significantly promoted; lipids in the lipogel acted as drug holders on the pNIPAM scaffold carrier and prolonged the calcein release process from 10 min to 2 h. Furthermore, the loading and release of calcein could be effectively controlled by modulating the relative amount of lipids incorporated in the lipogel, which can be realized by the salt-induced lipid release of the lipogel.

As a mature two-dimensional (2D) semiconductor, GeS has attracted huge interest due to its potential for wide applications in optical and electrical devices. However, research on the quantum transport of monolayer (ML) GeS field-effect transistors (FETs) is still lacking so far. In this work, we comprehensively reveal the ballistic transport performance and gate control mechanism of sub-10 nm ML GeS metal−oxide−semiconductor FETs (MOSFETs) by ab initio quantum transport simulation, including on-state current, subthreshold swing, intrinsic delay time, and power consumption. The on-state current of GeS p-MOSFETs (L g = 4.0−8.8 nm) along the armchair direction distinctly exceeds the high-performance requirements of the 2013 International Technology Roadmap for Semiconductors, and the p-devices along the zigzag direction perform well in the lowpower applications. Encouragingly, by adopting underlap structures, the ballistic transport performance of GeS MOSFETs can be further developed until the gate length decreases to 2.0 nm. Furthermore, compared with the previous typical 2D semiconductor MOSFETs, ML GeS MOSFETs exhibit superior competitiveness with short-channel length. We infer that the GeS monolayer will become a promising candidate for the short-channel material of transistors.

A type of microgel composite consisting of pNIPAM microspheres and rGO nanoparticles shows both photo- and thermo-responsive drug release behaviors.