A universal strategy is developed to construct a cascade Z‐Scheme system, in which an effective energy platform is the core to direct charge transfer and separation, blocking the unexpected type‐II charge transfer pathway. The dimension‐matched (001)TiO2‐g‐C3N4/BiVO4 nanosheet heterojunction (T‐CN/BVNS) is the first such model. The optimized cascade Z‐Scheme exhibits ≈19‐fold photoactivity improvement for CO2 reduction to CO in the absence of cocatalysts and costly sacrificial agents under visible‐light irradiation, compared with BVNS, which is also superior to other reported Z‐Scheme systems even with noble metals as mediators. The experimental results and DFT calculations based on van der Waals structural models on the ultrafast timescale reveal that the introduced T as the platform prolongs the lifetimes of spatially separated electrons and holes and does not compromise their reduction and oxidation potentials.

Developing high‐quality electret layer is important for the fabrication of high‐performance nonvolatile organic field effect transistor memory devices (OFET‐NVMs). In this work, three representative aromatic diimide frameworks are employed for comparative studies as n‐type doping materials for the electret layers in OFET‐NVMs, which are naphthalene diimide (NDI), perylene diimide (PDI), and pyrene diimide (PyDI). When blended with polystyrene (PS) to prepare the electret layers, all the memory devices containing aromatic diimide dopants exhibited significantly improved performances compared with the undoped counterparts, indicating that low‐lying LUMO energy levels of these dopants are beneficial for charge injection. All the devices with n‐type dopants exhibited long retention times (more than 104 s) and good switching reliability in more than 400 continuous write‐read‐erase‐read cycles. Among them, the PyDI‐based memory device exhibited superior performance compared with other aromatic diimides, which achieved a memory window of 34.0 V, a trapping charge density of 1.98 × 1012 cm−2 along with an on/off ratio higher than 104. This work indicates that PyDI framework could be a new platform for the future design of n‐type dopant for high‐performance nonvolatile organic field‐effect transistor memory devices.

Numerous traditional adhesives have good adhesion in dry environments. However, non-environmental-friendliness and poor water resistance largely limit their practical applications. To prepare biocompatible adhesives with strong water resistance and adhesion strength, in this paper, catechol-functionalized cellulose-based adhesive polymers are synthesized by grafting N-(3,4-dihydroxyphenethyl)methacrylamide and methyl methacrylate onto cellulose chain through atom transfer radical polymerization (ATRP). The successful synthesis of the catechol-functionalized cellulose-based adhesive polymers is confirmed by FTIR and 1 H NMR. The different characteristics of the adhesive polymers, such as thermal stability, swelling ratio, biocompatibility, and adhesion strength are investigated. Strong water resistance on various substrates is realized in underwater environment for the catechol-functionalized cellulose-based adhesive with addition of Fe 3+ . The adhesion strength and thermal stability are enhanced when the catechol content is increased. The adhesive with catechol content of 25.4% shows the adhesion strength of 0.45 MPa for iron substrate in underwater environment. In addition, the adhesive with addition of Fe 3+ exhibits excellent adhesion in dry environment, with maximum adhesion strength of 3.50 MPa for iron substrate. The cell culture test shows that the adhesive polymers have excellent biocompatibility. The biocompatible adhesives with strong water resistance have potential application in electronic, wood, and building fields.

A universal strategy is developed to construct a cascade Z‐Scheme system, in which an effective energy platform is the core to direct charge transfer and separation, blocking the unexpected type‐II charge transfer pathway. The dimension‐matched (001)TiO2‐g‐C3N4/BiVO4 nanosheet heterojunction (T‐CN/BVNS) is the first such model. The optimized cascade Z‐Scheme exhibits ≈19‐fold photoactivity improvement for CO2 reduction to CO in the absence of cocatalysts and costly sacrificial agents under visible‐light irradiation, compared with BVNS, which is also superior to other reported Z‐Scheme systems even with noble metals as mediators. The experimental results and DFT calculations based on van der Waals structural models on the ultrafast timescale reveal that the introduced T as the platform prolongs the lifetimes of spatially separated electrons and holes and does not compromise their reduction and oxidation potentials.

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