In conventional studies of heterogeneous photocatalytic oxidation, it is crucial to evaluate by means of control experiments the relevance of the “non‐catalyzed” autoxidation reaction under irradiation. If the autoxidation is found to be negligible, it is usually considered that it can be safely disregarded. However, in the case of aromatic aldehydes’ synthesis such as benzaldehyde, irradiating with UV light may lead to a more complex mechanism than previously thought. Herein, we prove that neglecting the autoxidative reaction can lead to a misinterpretation of the mechanism as well as an overestimation of the catalyst's efficiency, even if the control experiment exhibits zero yield. As an example, we studied the synthesis of benzaldehyde from benzyl alcohol by UV‐A irradiation with and without TiO2 and CdS nanoparticles; without catalyst, after a long induction time, the aldehyde enhances its own production through an autocatalytic reaction activated by the same light wavelengths utilized for the nanocatalysts. The long induction time leads to considering the autocatalysis to be deceptively negligible. However, the nanoparticles act as a fast initiator of the benzaldehyde autocatalysis, in such a way that the oxidation rate reached a similar performance with nanoparticles and after removing them. This suggests that the commonly ignored autocatalysis of benzaldehyde indeed is a relevant parallel pathway to the heterogeneous catalysis mechanism.

Two-dimensional CdS-based hybrid nanostructures are intriguing materials with an application prospect in different fields such as sensing (i. e., photoresistors) and solar energy harvesting (photocatalysis, photovoltaics, and so forth). We report herein a colloidal synthetic path for interfacing metal and semiconductor with 2D CdS nanoplates. Selective growth of Au, Pt, and a PtNi alloy as well as Cu 2−x S semiconductor is achieved on CdS nanoplates using controlled reduction of metallic precursors and thermal decomposition of a metal-sulfide single-source precursor using standard organic-phase colloidal chemistry.

Nanocrystal growth dynamics are investigated by a novel approach: real-time observation of nanocrystals in growth solutions using lab-scale in situ X-ray diffraction. The method reveals the evolution of crystal phase, size, shape, and composition.

The solution–liquid–solid (SLS) mechanism is a well-established method for forming one-dimensional (1D) nanostructures in a solution. Herein, an SLS mechanism is explored for the formation of metal oxides for the first time. Two key synthetic achievements allow this synthesis: (i) the design of a tailored catalyst with a low melting point and high stability and (ii) control over the reactivity and the oxidation of the precursors. Once these conditions are achieved, the SLS growth of indium and tin oxides ensues. Structural characterization of the products at various stages of the growth confirms the formation of 1D In2O3 and SnO2 nanoscale heterostructures using AuIn2 and Au7Sn3 as catalysts. Furthermore, SLS growth was easily adopted to insert SnO2 rods selectively between two domains of an Au/ZnO heterodimer, demonstrating the potential of achieving highly complex multicomponent metal-oxide nanostructures.

A wide range of nanoparticle properties can be tuned by changing their surface characteristics, especially when dealing with ultrathin nanomaterials. Surface modification with transition‐metal ions may affect a variety of the nanoparticles' properties including the surface charge, the electronic structure, and the electrical and optical characteristics. In this work, a surface study of ceria nanoparticles modified by attachment of various transition‐metal ions to their surface is conducted. Characterization of the decorated particles as well as of the modifying transition‐metal ion is carried out using zeta potential in organic solution, UV–Vis absorption, and electron paramagnetic resonance measurements, together with isothermal titration calorimetry, X‐ray photoelectron spectroscopy, and energy dispersive X‐ray spectroscopy. All measurements confirm the attachment of the cation to the surface of ceria, both in solid state and in colloidal suspension. It is suggested that the modifying ion‐complex attaches to ceria both via chemical or strong physical interactions and weak physical interactions, demonstrated by a case‐study modification of ceria using a copper‐oleylamine complex. The metalization has a significant effect on the surface charge of the nanoparticles by shifting the zeta potential to more positive values and on the optical properties of the modifying transition‐metal ions by red‐shifting their absorption peak.

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While the new cubic phase of tin monosulfide, π-SnS, shows potential for various applications, not much work was focused on the phase transitions, thermal stability, and thermal properties of π-SnS....