Halide perovskites have attracted surge of interest in the memristor field due to their superior electrical property and corresponding remarkable device performances. However, the issues of toxicity and unstable properties still severely restrict their potential applications. Here, the lead-free all-inorganic perovskite Cs₃Cu₂Br₅ films are adopted as the switching layer to fabricate memristors with Al/Cs₃Cu₂Br₅/ITO structure. The prepared Al/Cs₃Cu₂Br₅/ITO memristors exhibit typical reproducible bipolar resistive switching (RS) behavior with striking characteristics, including ultralow operating voltages (0.45, −0.39 V), moderate high resistance state/low resistance state ratio (≈10²), and remarkable retention time (>10⁴ s). In addition, the multilevel storage capability can be achieved by controlling compliance current. The RS effect, stemming from the formation/rupture of both localized conductive Br vacancy/Al atom filaments, is proposed to illustrate the memristors. More importantly, the RS behavior of Al/Cs₃Cu₂Br₅/ITO memristors maintains robustness in harsh environments with humidity up to 80%, enabling secure hardware applicable in extreme environments. This work demonstrates the opportunity for exploring the next-generation nonvolatile memories based on lead-free all-inorganic halide perovskites in future environmental-friendly and humidity robust electronics.

Implementation of tunable digital and analog resistive switching (RS) behaviors for memristors is crucial toward their development in data storage and energy-efficient computations. Herein, the CsPbBr3 film-based RS memristors with different switching film thickness and adaptable electrodes are constructed, which are implemented by the solution processed method. All the constructed memristors demonstrate stable bipolar switching behaviors, and in special, the gradual analog RS behavior with multi-level conductance is observed for the thin memristor, making it as the promising artificial synapse. As a comparison, the thick memristor demonstrates digital abrupt RS behavior, accompanying with a high memory window (>103), which can be applied in data storage field. Furthermore, the evolution of conductive filaments, stemming from synergetic bromine vacancies and aluminum atoms, is proposed to clarify the distinguished dynamic changes in the RS process. This work provides an optimization strategy to tune RS behavior for CsPbBr3-based RS memristors and paves the way for both data storage and artificial synapse applications.

We have demonstrated a photoelectrochemical solar-blind ultraviolet (UV) detector based on SrTiO ₃ (STO) nanocrystalline film in this work. The assembled UV detector presents a high on/off ratio of about 6433 under periodic UV irradiation, a high photocurrent density of 220.6 μ A cm ⁻² , and a fast response time of 9 ms. By introducing a block layer (BL) on fluorine-doped tin oxide substrate, the response and decay times are shortened to 6 ms and 8 ms, respectively. The BL plays a crucial part in hindering the recombination of electrons from electrolyte carriers and avoiding short circuits. Due to its excellent light capture capability, the detector based on SrTiO ₃ nanocrystalline exhibits high sensitivity to weak UV light (5 μ W cm ⁻² ). Moreover, the detector also exhibits visible-blind characteristics and a good linear response.

The photoelectrochemical (PEC) UV detector based on the traditional transparent conductive electrode (TCE) has a narrow response range due to the UV filtering effect. Here we prepared an Ag nanowire network by electrospinning and magnetron sputtering, and then transferred it to a quartz substrate to obtain a UV-visible TCE, which exhibits high transmittance of 80% in the UV region, and a very small sheet resistance of about 2 Ω sq⁻¹. An ITO functional layer is deposited to further improve the vertical electron conductivity and inhibit electronic recombination. After the photoactive layer was prepared by a sintering-free method, the PEC UV detector based on the new electrode system showed excellent self-powered response performance, including fast response, linear response and high sensitivity, and the response range of the device was greatly extended to 220–400 nm. Our work provides an effective strategy for solving the key problems of PEC UV detectors.

Hafnium oxide (HfOx) films are highly valued as functional layers in nonvolatile resistive switching (RS) memristors due to their scalability, compatibility with CMOS technology, and high dielectric constant. However, the low reliability of HfOx-based memristors is the key factor hindering their widespread practical applications. Herein, amorphous HfOx (a-HfOx) films are used as the switching layers to construct memristors, and the nitrogen treatment strategy is employed to enhance the switching characteristics. All the fabricated Al/a-HfOx/ITO memristors demonstrate bipolar digital RS behaviors, and specifically, the 500 °C-treated a-HfOx device exhibits highly reliable RS performance, including low cycle-to-cycle variability, concentrated distributions and low operating voltages, long-term retention capacity (>104 s), and good cycle endurance (>200 cycles). The mechanisms and physical models for enhanced switching performance are thoroughly elucidated, revealing that the formation of stable oxygen vacancy–dinitrogen complexes confines the conductive filament path and significantly reduces filament randomness during formation and rupture. This work renders an effective material engineering strategy for widening a path toward designing highly reliable nonvolatile data storage devices with striking switching performances.