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The disordered chain arrangement of polymer dielectrics has complex both internal and external effects on system performance, which generally stimulates the weak acquisition and grain boundaries of vapor‐deposited organic small molecule films (VDOSMFs) with thermally activated charge transport. As a result, achieving "band‐like" transmission of VDOSMs on polymer dielectrics is attempting to prove to be a major challenge. Three types of bi‐polymer dielectrics are developed to modulate charge transport from thermally activated mode to "band‐like" transport at the interfacial level. The bottom consisting of a polyimide layer is critical to interfacial modulation, which shows the selectively binding capability with up‐dielectric layers to realize the modulation of charge transport, as corroborated by interface characterization and density functional‐based tight‐binding calculation. The findings provide an effective strategy for modulating the charge transport through polymer dielectric engineering and also recommend a podium to further comprehend the electrical characteristics of small molecules in organic thin‐film transistors. [ABSTRACT FROM AUTHOR]

It is generally believed that the incorporation of fluorine functional groups into dielectrics can effectively impede the charge‐trapping process and improve carrier mobility. However, the relationship between the device performance and fluorinated groups is still not clear and also the modulation effect of fluorine functional groups on photogenerated charge carrier in phototransistors has not yet been investigated. Herein, phototransistors are constructed by using three kinds of gate dielectric layers with different fluorinated groups to exploit the effect of fluorine functional groups. It is concluded that the presence of fluorinated groups indeed increases the transistor mobility and optical figures of merit in phototransistors compared to the device with a fluorine‐free dielectric layer. Concurrently, the exciton binding energy is increased with the addition of fluorinated groups, resulting in the decrease of phototransistor performance compared with less content of fluorinated groups due to the synergistic balance effect of fluorine functional groups. The results further clarify how the fluorine functional groups optimize the interface of organic phototransistors and modulate the photoelectric performance. [ABSTRACT FROM AUTHOR]

The limited stability, compatibility, and ion transport capacity of SEI remain key challenges in the development of high-energy–density sodium metal batteries. In order to realize the rational design and facile synthesis of SEI, the influencing factors of different challenges were systematically sorted out. By improving SEI chemical/electrochemical stability, mechanical stability, and thermal stability, the voltage window and temperature range of the battery operation can be effectively broadened. Suppressing the volume effect, phase exfoliation, and phase dissolution to enhance SEI compatibility is crucial for extending battery cycle life. The stability of ion transport at the electrode–electrolyte interface is affected by the composition, structure, and homogeneity of the interfacial phase, and fast and uniform interfacial Na+ transport can enable high-rate, high-safety sodium ion battery designs. [Display omitted] • The challenges and design elements of SEI are summarized comprehensively. • The formation mechanism, characteristics, and failure mechanism of SEI are systematically reviewed. • The latest development of SEI regulation strategy is discussed. • The opportunity and research direction of interface design for long lasting sodium metal batteries are prospected. Inhomogeneous and fragile solid electrolyte interphase (SEI) leads to poor battery cycle life and safety hazards, which is a key challenge that limits the practical application of low-cost sodium metal anodes. Although sodium metal batteries based on non-aqueous liquid and solid electrolytes have made great progress in terms of interfacial chemistry and SEI regulation strategies, the relevant evaluation of SEI from the perspective of the electrolyte is not well understood. This paper reviews the formation mechanism, physicochemical properties, and failure mechanism of SEI at the interface between the sodium metal and the liquid/solid electrolyte, focusing on poor stability, compatibility, interfacial ion transport problems, and influencing factors. Recent advances in SEI regulation are summarized in terms of electrolytes, artificial interphases, and electrode engineering to achieve ideal electrochemical reversibility. The effectiveness of the SEI engineering strategies was evaluated based on a comprehensive review of the interfacial stability in different electrolyte systems. Finally, the challenges associated with rational interface design for long-lasting sodium metal batteries are discussed, along with promising avenues for the same. [ABSTRACT FROM AUTHOR]