The consumer demand for emerging technologies such as augmented reality (AR), autopilot, and three-dimensional (3D) internet has rapidly promoted the application of novel optical display devices in innovative industries. However, the micro/nanomanufacturing of high-resolution optical display devices is the primary issue restricting their development. The manufacturing technology of micro/nanostructures, methods of display mechanisms, display materials, and mass production of display devices are major technical obstacles. To comprehensively understand the latest state-of-the-art and trigger new technological breakthroughs, this study reviews the recent research progress of master molds produced using nanoimprint technology for new optical devices, particularly AR glasses, new-generation light-emitting diode car lighting, and naked-eye 3D display mechanisms, and their manufacturing techniques of master molds. The focus is on the relationships among the manufacturing process, microstructure, and display of a new optical device. Nanoimprint master molds are reviewed for the manufacturing and application of new optical devices, and the challenges and prospects of the new optical device diffraction grating nanoimprint technology are discussed.

Inorganic nanocarriers are potent candidates for delivering conventional anticancer drugs, nucleic acid-based therapeutics, and imaging agents, influencing their blood half-lives, tumor targetability, and bioactivity. In addition to the high surface area-to-volume ratio, they exhibit excellent scalability in synthesis, controllable shape and size, facile surface modification, inertness, stability, and unique optical and magnetic properties. However, only a limited number of inorganic nanocarriers have been so far approved for clinical applications due to burst drug release, poor target specificity, and toxicity. To overcome these barriers, understanding the principles involved in loading therapeutic and imaging molecules into these nanoparticles (NPs) and the strategies employed in enhancing sustainability and targetability of the resultant complexes and ensuring the release of the payloads in extracellular and intracellular compartments of the target site is of paramount importance. Therefore, we will shed light on various loading mechanisms harnessed for different inorganic NPs, particularly involving physical entrapment into porous/hollow nanostructures, ionic interactions with native and surface-modified NPs, covalent bonding to surface-functionalized nanomaterials, hydrophobic binding, affinity-based interactions, and intercalation through co-precipitation or anion exchange reaction.

We present a straightforward method for one-pot electrodeposition of platinum atoms-doped molybdenum oxide (Pt·MoO_3−x) films and show their superior electrocatalytic activity in the hydrogen evolution reaction (HER). A ~15-nm-thick Pt·MoO_3−x film was prepared by one-pot electrodeposition at −0.8 V for 1 ms. Due to considerably different solute concentrations, the content of Pt atoms in the electrodeposited composite electrocatalyst is low. No Pt crystals or islands were observed on the flat Pt·MoO_3−x films, indicating that Pt atoms were homogeneously dispersed within the MoO_3−x thin film. The catalytic performance and physicochemical features of Pt·MoO_3−x as a HER electrocatalyst were characterized. The results showed that our Pt·MoO_3−x film exhibits 23- and 11-times higher current density than Pt and MoO_3−x electrodeposited individually under the same conditions, respectively. It was found that the dramatic enhancement in the HER performance was principally due to the abundant oxygen defects. The use of the developed one-pot electrodeposition and doping method can potentially be extended to various catalytically active metal oxides or hydroxides for enhanced performance in various energy storage and conversion applications.

Research on glass nanocomposites (GNCs) has been very active in the past decades. GNCs have attracted — and still do — great interest in the fields of optoelectronics, photonics, sensing, electrochemistry, catalysis, biomedicine, and art. In this review, the potential applications of GNCs in these fields are briefly described to show the reader the possibilities of these materials. The most important synthesis methods of GNCs (melt-quenching, sol-gel, ion implantation, ion-exchange, staining process, spark plasma sintering, radio frequency sputtering, spray pyrolysis, and chemical vapor deposition techniques) are extensively explained. The major aim of this review is to systematize our knowledge about the synthesis of GNCs and to explore the mechanisms of formation and growth of NPs within glass matrices. The size-controlled preparation of NPs within glass matrices, which remains a challenge, is essential for advanced applications. Therefore, a thorough understanding of GNC synthesis techniques is expected to facilitate the preparation of innovative GNCs.

Hollow nanospheres exhibit unique properties and find a wide interest in several potential applications such as drug delivery. Herein, novel hollow bioactive glass nanospheres (HBGn) with large hollow cavity and large mesopores in their outer shells were synthesized by a simple and facile one-pot ultrasound assisted sol‒gel method using PEG as the core soft-template. Interestingly, the produced HBGn exhibited large hollow cavity with ~43 nm in diameter and mesoporous shell of ~37 nm in thickness and 7 nm pore size along with nanosphere size around 117 nm. XPS confirmed the presence of Si and Ca elements at the surface of the HBGn outer shell. Notably, HBGn showed high protein loading capacity (~570 mg of Cyto c per 1 g of HBGn) in addition to controlled protein release over 5 d. HBGn also demonstrated a good in vitro capability of releasing calcium (Ca²⁺: 170 ppm) and silicate (SiO₄⁴⁻: 78 ppm) ions in an aqueous medium over 2 weeks under physiological-like conditions. Excellent in vitro growth of bone-like hydroxyapatite nanocrystals was exhibited by HBGn during the soaking in SBF. A possible underlying mechanism involving the formation of spherical aggregates (coils) of PEG was proposed for the formation process of HBGn.

The SnO₂-based family is a traditional but important gas-sensitive material. However, the requirement for high working temperature limits its practical application. Much work has been done to explore ways to improve its gas-sensing performance at room temperature (RT). For this report, SnO₂, SnO, and SnO/SnO₂ heterojunction was successfully synthesized by a facile hydrothermal combined with subsequent calcination. Pure SnO₂ requires a high operating temperature (145 °C), while SnO/SnO₂ heterojunction exhibits an excellent performance for sensing NO₂ at RT. Moreover, SnO/SnO₂ exhibits a fast response, of 32 s, to 50 ppm NO₂ at RT (27 °C), which is much faster than that of SnO (139 s). The superior sensing properties of SnO/SnO₂ heterojunction are attributed to the unique hierarchical structures, large number of adsorption sites, and enhanced electron transport. Our results show that SnO/SnO₂ heterojunction can be used as a promising high-performance NO₂ sensitive material at RT.

The low surface area, high recombination rate of photogenerated charge carriers, narrow visible range activity, and difficulty in the separation from cleaned solutions limit the wide application of g-C₃N₄ as a photocatalyst. Herein, we have succeeded in developing a one-pot strategy to overcome the above-mentioned difficulties of g-C₃N₄. The broadening of the visible-light response range and inducing magnetic nature to g-C₃N₄ was succeeded by preparing a nanocomposite with Fe₂O₃ via a facile solvothermal method. The preparation method additionally imparted layer exfoliation of g-C₃N₄ as evident from the XRD patterns and TEM images. The strong interaction between the components is revealed from the XPS analysis. The broadened visible-light absorbance of Fe₂O₃/g-C₃N₄ with a Z-scheme photocatalytic degradation mechanism is well evident from the UV‒Vis DRS analysis and PL measurement of the composite with terephthalic acid. The active species of photocatalysis were further investigated using scavenging studies in methylene blue degradation that revealed hydroxyl radicals and holes as the major contributors to the activity of Fe₂O₃/g-C₃N₄.

Non-noble metal electrocatalysts for water cracking have excellent prospects for development of sustainable and clean energy. Highly efficient electrocatalysts for the oxygen evolution reaction (OER) are very important for various energy storage and conversion systems such as water splitting devices and metal‒air batteries. This study prepared a NiMo₄@C₃N₄ catalyst for OER and hydrogen evolution reaction (HER) by simple methods. The catalyst exhibited an excellent OER activity based on the response at a suitable temperature. To drive a current density of 10 mA·cm⁻² for OER and HER, the overpotentials required for NiMo₄@C₃N₄-800 (prepared at 800 °C) were 259 and 118 mV, respectively. A two-electrode system using NiMo₄@C₃N₄-800 needed a very low cell potential of 1.572 V to reach a current density of 10 mA·cm⁻². In addition, this catalyst showed excellent durability after long-term tests. It was seen to have good catalytic activity and broad application prospects.

Electroactive hydrogels could guide the regeneration of nerves and promote their functional recovery. An aniline pentamer-crosslinked chitosan (CS-AP) hydrogel with better electroactivity and degradation was fabricated by the carbodiimide method, and then injected into the repair site of sciatic nerve damage, with its gelation time, tensile strength, and conductivity reaching 35 min, 5.02−6.69 MPa, and from 2.97 × 10⁻⁴ to 3.25 × 10⁻⁴ S·cm⁻¹, respectively, due to the cross-linkage and well-distribution of AP. There was better cytocompativility of CS-AP hydrogel on nerve cells. The results of the in vivo repair indicated that CS-AP10 hydrogel induced the capillaries formation and the repair of sciatic nerve defect, and re-innervated gastrocnemius muscle in the CS-AP10 group were obviously better than other experimental groups, due to the electroactivity of CS-AP and its degradation into fragments. These results indicated the potential application of CS-AP hydrogel in the regeneration and function recovery of peripheral nerve injury.

Heusler alloys are a kind of intermetallic compounds with highly-ordered arrangement of atoms. Many attractive functional materials have been developed in Heusler alloys. Due to the application requirements of materials in new-generation electronic devices and spintronics devices, one-dimensional nanostructured Heusler alloys with special functions are needed. In this work, it is proposed to grow one-dimensional Heusler alloy nanostructures (1D-HA-NSs) by magnetron sputtering plus anodic aluminum oxide (AAO) template. Nanowires with different shapes, amorphous-coated (AC) nanowires and nanotubes were successfully grown for several Heusler alloys. AC nanowires are the unique products of our method. Heusler alloy nanotubes are reported for the first time. The one-dimensional nanostructures grow on the surface of the AAO substrate rather than in the holes. The top of the pore wall is the nanostructure growth point, the shape of which determines the morphology of the nanostructures. A general growth mechanism model of one-dimensional nanostructures on AAO template was established and further confirmed by experimental observation.