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In this work, we have systematically characterized the ferroelectric (FE) and memory properties in the fully depleted silicon-on-insulator (FDSOI) FE field-effect transistor (FeFET) across a temperature range of 300–5 K. At a deep cryogenic temperature of 5 K, the endurance of multipolarization states in Hf0.5Zr0.5O2 (HZO) gate-stack exhibits a significant improvement compared to that at 300 K. Especially for states of partial switching polarization under low voltage, it is expected to achieve endurance immunity. This can be attributed to that oxygen vacancies are more difficult to redistribute at cryogenic temperature. Furthermore, compared to 300 K, the performance of multilevel cell FDSOI FeFET at 5 K demonstrates higher stability, providing a promising solution for cryogenic memory and computing systems with low power and high stability.

The presence of ethanol as an impurity in industrial methanol significantly degrades the quality of the downstream products. Addressing the challenge of suppressing ethanol formation remains crucial in the synthesis of industrial methanol. In this context, we systematically characterized a series of commercial catalysts and evaluated their catalytic performance for methanol synthesis to elucidate the relationship between the catalyst structure and ethanol selectivity. Our performance tests indicate that the Cu–Zn–Al commercial catalyst (NG), enhanced with a ZrO2promoter, can effectively inhibit ethanol formation, reducing it to approximately 580 ppm after 1000 h. The ZrO2promoter stabilizes Cu0, ensuring it is highly dispersed and maintains a homogeneous structure, which is pivotal for the catalyst’s exceptional performance. Analysis through temperature-programmed desorption and density functional theory (DFT) demonstrates that the high dispersity of Cu0enhances the adsorption of CO and H2. Additionally, a uniform Cu0active site structure contributes to the increased methanol selectivity while simultaneously suppressing ethanol formation. This study underscores the significant potential of incorporating a ZrO2promoter in catalysts to effectively suppress ethanol production under industrial operating conditions.

We have experimentally studied resistance switching and carrier transport mechanisms of HfO2-based ferroelectric diode (FD) by systematic measurement as well as current fitting with possible carrier transport models. FD with TiN/HZO/Al2O3/IGZO structure is fabricated with a low thermal budget of 400 °C and exhibits robust memory and self-rectifying characteristics. Fitting results show that current in high-resistance state (HRS) follows thermionic emission (TE), while low-resistance state (LRS) is dominated by Poole–Frenkel (PF) emission. The switching between HRS and LRS is attributed to ferroelectric polarization switching combined with sufficient electron trapping. This work provides fundamental understanding of device physics of HfO2-based FD for high-density and low-power memory applications.

Conjugated polymers with both high charge mobilities and responsive functionality have received increasing attention because of their promising applications in organic electronic devices and chemo-/biosensors. We successfully incorporated thymine groups in the side chains of diketopyrrolopyrrole (DPP)-based conjugated polymer PDPP4T-T. Our studies reveal that thin films of PDPP4T-Texhibit improved crystallinity and higher charge mobility compared with analogous polymers with pure alkyl chains. This is attributed to the formation of H-bonding among thymine groups, which could strengthen interchain interactions and thus facilitate an ordered packing of polymer chains. Importantly, thin films of PDPP4T-Tcontaining either Pd(II)or Hg(II)ions were successfully fabricated via air–water interface coordination reactions of thymine groups with ions. Thin-film field-effect transistors (FETs) of PDPP4T-Tcontaining Pd(II)ions exhibit a sensitive and selective response toward CO even at a low concentration of 10 ppb. Such an FET-based CO sensor with high sensitivity and good selectivity is achieved for the first time by using polymeric semiconductors. Alternatively, FETs with PDPP4T-T-Hg(II)thin films can be utilized to detect H2S with good selectivity and high sensitivity (down to 1 ppb). Therefore, incorporating thymine groups into conjugated polymers can not only improve semiconducting mobilities but also endow semiconducting thin films with sensing functionality.