One-dimensional In 2 O 3 (ZnO) m superlattice wires were first synthesized on silicon substrates by evaporating a mixture of In and ZnO powders. The high-resolution transmission electron microscopy image indicates that the wires have a superlattice structure along their length, which consists of alternating stacks of an InO 2 octahedral layer, as an inversion boundary, and an InO + (ZnO) m slab. Each slab is further separated by many triangular (zigzag) shape-contrast boundaries. They are secondary polarity inversion boundaries formed by 5-fold coordinated In and Zn atoms. The formation of such superlattice nanostructures is explained by the zigzag model. The PL properties of the superlattice nanostructures are discussed with regard to its temperature dependence for the first time.

Indium-doped ZnO nanospirals were synthesized by one-step thermal evaporation. Transmission electron micrographs show that the nanospirals are structurally uniform and free of defects. The helical nanostructures, which are constructed by rolling nanobelts grown along the ͗1010͘ direction with the Ϯ͑0001͒ polar planes as the dominate surfaces, are energetically favored in terms of the electrostatic polar charge model. The typical radius of curvature of the nanospirals is several micrometers. The In-doped nanospirals are expected to have interesting optoelectronic and mechanical properties and could be potential building blocks in nanoscale optoelectronic and electromechanical systems.

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Films with excellent flexibility and mechanical stability are important for flexible and wearable devices. However, most films reported are prepared on substrates, and the synthesis of freestanding flexible films remains a challenge. Herein, a freestanding Bi2S3 nanofibrous membrane (NFM) is successfully prepared via a one‐step hydrothermal method, which is self‐assembled from ultralong Bi2S3 nanowires (NWs) over a length of millimeter‐scale crisscrossing each other. Significantly, the Bi2S3 NFM can be bent or clipped into an arbitrarily desired form. Based on the freestanding Bi2S3 NFM, an IR photodetector is fabricated, depicting a robust responsivity of 2.23 (2.06) µA W−1 under 850 (940) nm illumination. The Bi2S3 NFM photodetector exhibits a relatively fast response time (47.1 ms), which is attributed to high‐speed carrier transport efficiency in the NWs network. Under the bending states, the device still exhibits excellent detection performance, maintaining more than 86% of the initial photocurrent even after 1000 bending‐flattening times. The robust photoresponse of the Bi2S3 NFM photodetector after 2 months of storage in air and after 1 week in the bending state illustrates its excellent air stability and flexible detection ability. Besides, the photodetector can clearly identify the target image, indicating widespread potential applications in flexible and wearable fields.