We synthesized uniform pore-sized mesoporous silica spheres embedded with magnetite nanocrystal and quantum dots. The magnetic separation, luminescent detection, and controlled release of drugs were demonstrated using the uniform mesoporous silica spheres embedded with monodisperse nanocrystals.

Nanostructured magnetic materials (NMMs) [1] have attracted much attention recently because of their broad biotechnological applications including support matrices for enzyme immobilization, [2] immunoassays, [3] drug delivery, [4] and biosensors.[5]

The development of energy-conversion devices using water movement has actively progressed. Ionovoltaic devices, which are driven by ion dynamics, show ion specificity by which different ions with identical charges show different output performance. However, the ion specificity remains poorly understood because the influence of the ion species on generated electric signals is not elucidated. The ion specificity in electric signals induced by flowing water droplet was investigated in terms of its relationship with the potential profile across the solid-liquid interface.

Meso-structured onion-like silica (Meso-Onion-S) was synthesized and used as a host of enzyme immobilization. Meso-Onion-S has a 200–300 nm sized primary meso-structured onion building unit, and each onion unit has highly curved mesopores of 10 nm diameter in a multishell structure. Nanoscale enzyme reactors (NERs) in Meso-Onion-S were prepared via a two-step process of enzyme adsorption and subsequent enzyme cross-linking, which effectively prevents the leaching of cross-linked enzyme aggregates from highly curved mesopores of Meso-Onion-S. As a result, NERs in Meso-Onion-S significantly improved the enzyme stability as well as the enzyme loading. For example, NER of lipase (NER-LP) was stable under rigorous shaking for 40 days, while the control sample of adsorbed LP (ADS-LP) with no enzyme cross-linking showed a rapid inactivation due to rigorous enzyme leaching under shaking. Stable NER-LP was successfully employed to produce biodiesels and fatty acid methyl esters, from the LP-catalyzed transesterification of soybean oil with methanol. Interestingly, the specific activity of NER-LP was 23 and 10 times higher than those of free LP and ADS-LP, respectively, revealing the importance of LP stabilization in the form of NER-LP in the presence of organic solvents.

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Phase transition and coexistence of 2H (trigonal prismatic structure) and 1T′ (distorted octahedral structure) phases occur easily in molybdenum ditelluride (MoTe 2 ) when compared with other 2D MX 2 type (M = Mo, W and X = S, Se) transition metal dichalcogenides (TMDs) because of small discrepancies in the cohesive energy. [1][2][3][4] Phase-engineered 2D TMDs, particularly MoTe 2 films including 2H, 1T′, and 1T phases, are very attractive candidates for numerous electronic applications, such as ambipolar field-effect transistors (FETs), environmental sensors, superconductors, spintronics, and valley optoelectronics. [5][6][7][8] Atomically thin-layer 2H MoTe 2 possesses a narrow bandgap energy of 1 eV in comparison to the bandgap energy (1.89 eV) of monolayer MoS 2 and is a potential candidate for various optoelectronic device applications, such as solar cells and photodetectors. [3,8,9] From the electronic device application point of view, the 2H and the 1T phases, i.e., semiconducting and semimetal MoTe 2 are applicable as a 2D materials beyond molybdenum disulfide such as molybdenum ditelluride (MoTe 2 ) have attracted increasing attention because of their distinctive properties, such as phase-engineered, relatively narrow direct bandgap of 1.0-1.1 eV and superior carrier transport. However, a wafer-scale synthesis process is required for achieving practical applications in next-generation electronic devices using MoTe 2 thin films. Herein, the direct growth of atomically thin 1T′, 1T′-2H mixed, and 2H phases MoTe 2 films on a 4 in. SiO 2 /Si wafer with high spatial uniformity (≈96%) via metal-organic vapor phase deposition is reported. Furthermore, the wafer-scale phase engineering of few-layer MoTe 2 film is investigated by controlling the H 2 molar flow rate. While the use of a low H 2 molar flow rate results in 1T′ and 1T′-2H mixed phase MoTe 2 films, 2H phase MoTe 2 films are obtained at a high H 2 molar flow rate. Field-effect transistors fabricated with the prepared 2H and 1T′ phases MoTe 2 channels reveal p-type semiconductor and semimetal properties, respectively. This

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