Shape-Controlled Synthesis of Dumbbell-like Pt-Fe3O4-MnO x Nanoparticles by Governing the Reaction Kinetics

Magnetite-based Janus nanoparticles, their synthesis and biomedical applications

The advent of Janus nanoparticles has been a great breakthrough in the emerging field of nanomaterials. Janus nanoparticles refer to a single structure with two distinct chemical functions on either side. Owing to their asymmetric structures, they can be utilized in a variety of applications where monomorphic particles are insufficient. In the last decade, a wide variety of materials have been employed to fabricate Janus nanoparticles, and due to the great advantages of magnetite (Iron-oxide) NPs, they have been considered as one of the best candidates. With the main benefit of magnetic controlling, magnetite Janus nanoparticles fulfill great promises, especially in biomedical areas such as bioimaging, cancer therapies, theranostics, and biosensing. The intrinsic characteristics of magnetite Janus nanoparticles (MJNPs) even hold great potential in magnetite Janus forms of micro-/nanomotors. Despite the great interest and potential in magnetic Janus NPs, the need for a comprehensive review on MJNPs with a concentration on magnetite NPs has been overlooked. Herein, we present recent advancements in the magnetite-based Janus nanoparticles in the flourishing field of biomedicine. First, the synthesis and fabrication methods of Janus nanoparticles are discussed. Then we will delve into their intriguing biomedical applications, with a separate section for magnetite Janus micro-/nanomotors in biomedicine. And finally, the challenges and future outlook are provided. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > In Vitro Nanoparticle-Based Sensing.

Metal/semiconductor interfaces in nanoscale objects: synthesis, emerging properties and applications of hybrid nanostructures

Hybrid nanostructures, composed of multi-component crystals of various shapes, sizes and compositions are much sought-after functional materials. Pairing the ability to tune each material separately and controllably combine two (or more) domains with defined spatial orientation results in new properties. In this review, we discuss the various synthetic mechanisms for the formation of hybrid nanostructures of various complexities containing at least one metal/semiconductor interface, with a focus on colloidal chemistry. Different synthetic approaches, alongside the underlying kinetic and thermodynamic principles are discussed, and future advancement prospects are evaluated. Furthermore, the proved unique properties are reviewed with emphasis on the connection between the synthetic method and the resulting physical, chemical and optical properties with applications in fields such as photocatalysis.

Dumbbell-like Pt-Fe3O4 Nanoparticles Encapsulated in N-Doped Carbon Hollow Nanospheres as a Novel Yolk@Shell Nanostructure toward High-Performance Nanocatalysis

Noble metal-Fe₃O₄ dumbbell-like nanoparticles have aroused considerable attention because of their high potential as heterogeneous nanocatalysts. The designed synthesis of the advanced architecture of noble metal-Fe₃O₄ dumbbell-like nanoparticles with both improved catalytic activity and stability is still a challenge. Herein, through the combination of yolk@shell and dumbbell-like nanostructures, dumbbell-like Pt-Fe₃O₄ nanoparticles encapsulated in N-doped carbon hollow nanospheres (Pt-Fe₃O₄@N-carbon) as a special yolk@shell nanostructure were developed. In comparison with Pt-Fe₃O₄ dumbbell-like nanoparticles, Pt-Fe₃O₄@N-carbon yolk@shell nanoparticles showed improved catalytic activity and stability toward the liquid-phase 4-nitrophenol reduction and β-ionone oxidation, making them a promising candidate for catalysis applications.

PdO/ZnO@mSiO2 Hybrid Nanocatalyst for Reduction of Nitroarenes

Development of a novel approach for synthesizing nanostructured catalysts and achieving further improvements in catalytic activity, effectiveness, and efficiency remains a major challenge. In this report, we describe the preparation of a nanostructured PdO/ZnO@mSiO2 hybrid nanocatalyst featuring well-dispersed PdO nanoparticles within hollow ZnO@mSiO2. The as-prepared PdO/ZnO@mSiO2 hybrid nanocatalyst exhibited good morphological features, derived from the controlled stepwise synthesis from Pd/PS@ZIF-8@mSiO2 (PS = polystyrene). The morphology, size, oxidation state, crystallinity, and thermal stability of the prepared PdO/ZnO@mSiO2 hybrid nanocatalyst were confirmed by a series of physicochemical techniques. The PdO/ZnO@mSiO2 hybrid nanocatalyst showed very high catalytic efficiency in the reduction of 4-nitrophenol and various nitroarenes under eco-friendly conditions. Therefore, the PdO/ZnO@mSiO2 hybrid nanocatalyst is a promising alternative catalyst for applications in environmental remediation.