Low-cost multicomponent alloyed one-dimensional (1D) semiconductors exhibit broadband absorption from the ultraviolet to the near-infrared regime, which has attracted a great deal of interest in high-performance flexible optoelectronic devices. Here, we report the facile one-step fabrication of high-performance broadband rigid and flexible photodevices based on multicomponent alloyed 1D cadmium–sulfur–selenide (CdS x Se1–x ) micro-nanostructures obtained via a vapor transport route. Photoresponse measurements have demonstrated their superior spectral photoresponsivity (5.8 × 104 A/W), several orders of magnitude higher than the pristine CdSe nanobelt photodevice, high specific detectivity (2 × 1015 Jones), photogain (1.2 × 105), external quantum efficiency (EQE, 1.4 × 107%), rapid response speed (13 ms), and excellent long-term environmental stability. The multicomponent alloyed CdS x Se1–x nanobelt photodevice demonstrated about three times higher photocurrent as well as can operate under multiple color illuminations (200–800 nm) and at a high applied bias of 10 V with the photoresponsivity and EQE being boosted to 4.34 × 105 A/W and 8.96 × 107%, respectively. Furthermore, multicomponent alloyed CdS x Se1–x nanobelt flexible photodevices show excellent mechanical and flexural photostabilities with identical photoresponse as rigid nanodevices. The improvement mechanism found in the present research can be exploited to lead to the design of high-performance flexible photodevices comprising other multicomponent nanomaterials.

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TiO2, as a potential anode for lithium-ion batteries, suffers from low theoretical capacity and inferior reaction kinetics. Herein, we innovatively designed a unique dual-Schottky regulated ternary defective-TiO2-supported Co-nanodots-anchored N-doped-carbon-coated (defective TiO2@Co@NC) electrode, which was expected to possess advanced electrochemical reaction kinetics and increased Li-ion capacity. Molecular mechanics calculations indicated that the isolated cobalt nanodot can be stably formed in defective TiO2@Co@NC. And such a Co nanodot can not only firmly bridge the defective TiO2 matrix and Co-embedded N-doped carbon coating forming a dual-Schottky heterostructure, which boosts the fast reaction kinetics, but also effectively suppress the irreversibility of Li-ion intercalation. Correspondingly, as-designed binder-free defective TiO2@Co@NC anode was successfully synthesized via carbonization of the 3D hierarchical defective TiO2@Co-MOF precursor. In particular, the defective TiO2 nanotube array was for the first time used as nonreactive template to prepare Co-MOF composites. And TEM characterizations revealed that plentiful isolated cobalt nanodots were factually formed in derivative defective TiO2@Co@NC. As expected, defective TiO2@Co@NC electrodes exhibit remarkably high areal capacity (1191.2 μAh cm–2/490.9 mAh g–1 at 100 μA cm–2/41 mA g–1, 2.8 times of the pristine anatase TiO2 anodes), excellent cyclic stability (a capacity fading rate of 0.026% per cycle, at 500 μA cm–2/206.0 mA g–1 for 600 cycles), and superb rate properties (405.0 μAh cm–2/166.9 mAh g–1 at 1000 μA cm–2/412.0 mA g–1). Furthermore, the realization of in situ growth of uniform Co-MOF coatings with controllable thickness in defective TiO2@Co-MOF precursors facilitates the preparation of defective TiO2@Co@NC derivatives with tailored specific capacities, which paves the way for future research on MOF composites and Li-ion batteries.

Non-volatile resistive random-access memory (RRAM) is being promoted as a possible alternative to flash memory, however the optimal material system and sophisticated fabrication techniques hinder its utilization in practical routes. Here, we demonstrate the direct fabrication of metal/oxides/semiconductor (MOS) structured Ag/VO2(B)/SiOx/n++Si RRAM via drop-coating process, in which bipolar resistive switching behavior was obtained and investigated systematically. The RRAM devices exhibit good cycle-to-cycle endurance (>30 cycles) and high on/off ratio (>60). The switching mechanism is proposed to form Ag conducting filaments via VO2(B) nanorods’ guide by comparing the resistive switching behavior of Ag/SiOx/n++Si, Ag/VO2(B)/n++Si, Ag/VO2(B)/SiOx/n++Si devices and the corresponding SEM images before and after the application of electric field, which is confirmed by introducing NaCl barrier layer in Ag/VO2(B)-NaCl/SiOx/n++Si devices. The present study may pave a convenient route for fabricating the ultrahigh density resistive memory devices without the aid of complex fabrication techniques, as well as provide a new potential material system for RRAM.

Despite numerous studies on broadband photodetectors, the problematic query that remains unaddressed is the limited photoresponsivity while broadening the spectral regime. Here, for the first time, a rational design of a hybrid 1D CdSe nanobelt/2D PbI 2 flake heterojunction device is constructed, which substantially boosts the photocurrent while significantly attenuating the dark current, resulting in improved photodetector figures-of-merit. Thanks to the excellent quality of the nanobelt/ flake and built-in electric field at the CdSe/PbI 2 interface heterojunction, photogenerated carriers are promptly segregated and more photoexcitons are accumulated by the respective electrodes, enabling a high responsivity of ∼10 6 A/W, making this one of the highest values among similar reported hybrid heterojunction photodetectors, together with a large linear dynamic range, superior sensitivity, excellent detectivity and external quantum efficiency, an ultrafast response, and a broadband spectral response range. The similar 1D/2D hybrid heterojunction device architecture assembled on the flexible polyimide tape substrate exhibits excellent folding endurance and mechanical, flexural, and long-term environmental stability. The present device architecture and robust operational stability in an ambient environment reveals that the combination of the present 1D/2D hybrid heterojunction has incredible potential for future flexible photoelectronic devices.