We report direct photocatalytic hydrogen evolution from substoichiometric highly reduced tungsten oxide (WO x ) nanowires (NWs) using sacrificial alcohol. WO x NWs are synthesized via nonaqueous colloidal synthesis with a diameter of about 4 nm and an average length of about 250 nm. As-synthesized WO x NWs exhibit a broad absorption across the visible to infrared regions attributed to the presence of oxygen vacancies. The optical band gap is increased in these WO x NWs compared to stoichiometric bulk tungsten oxide (WO 3 ) powders as a result of the Burstein−Moss shift. As a consequence of this increase, we demonstrate direct photocatalytic hydrogen production from WO x NWs through alcohol photoreforming. The stable H 2 evolution on platinized WO x NWs is observed under conditions in which platinized bulk WO 3 and bulk WO 2.9 powders either do not show activity or show very low rates, suggesting that increased surface area and specific exposed facets are key for the improved performance of WO x NWs. This work demonstrates that control of size and composition can lead to unexpected and beneficial changes in the photocatalytic properties of semiconductor materials.

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Lead-free cesium bismuth bromide perovskite nanocrystals are synthesized via the heating-up method with tailored morphology and optical properties.

Immiscible solvent treatment induced oriented attachment of perovskite nanocrystal, resulting in change of size and dimensionality (0D/1D/2D).

Breakthroughs in the biomedical and regenerative therapy fields have led to the influential ability of stem cells to differentiate into specific types of cells that enable the replacement of injured tissues/organs in the human body. Non-destructive identification of stem cell differentiation is highly necessary to avoid losses of differentiated cells, because most of the techniques generally used as confirmation tools for the successful differentiation of stem cells can result in valuable cells becoming irrecoverable. Regarding this issue, recent studies reported that both Raman spectroscopy and electrochemical sensing possess excellent characteristics for monitoring the behavior of stem cells, including differentiation. In this review, we focus on numerous studies that have investigated the detection of stem cell pluripotency and differentiation in non-invasive and non-destructive manner, mainly by using the Raman and electrochemical methods. Through this review, we present information that could provide scientific or technical motivation to employ or further develop these two techniques for stem cell research and its application.

all-inorganic ternary perovskite nanocrystals (NCs) are widely studied for their promising characteristics as semiconducting materials for optoelectronic applications owing to their high photoluminescence (PL) quantum yields (PLQYs) and narrow emission bandwidths. [3] The optical properties of perovskite NCs can be tuned by tailoring their sizes, compositions, and confined dimensions. [4][5][6][7] In addition to size confinement on the nanoscale, the dimensionality of ternary metal halides can be defined based on the arrangement of the [BX 6 ] octahedral units in the crystal structure. [8,9] Lattice distortion occurs within the metal halide structure depending on the size of the elements or the coordination number of the A cations. This induces either a two-or 1D arrangement, wherein the [BX 6 ] octahedra are linked in two directions or one direction, respectively, or complete isolation of the octahedral units (0D). [10][11][12] Among these, 0D materials have recently attracted considerable attention because their unique optical and electronic properties are distinct from those of 3D metal halide perovskite structures. [13] Specifically, 0D metal halide materials have electronically separated polyhedra or clusters resulting in a large bandgap, low conductivity, and low mobility. [8,14,15] In addition, these materials show enhanced radiative recombination owing to the self-trapping of excitons [16,17] or defects [18,19] in the spatially isolated octahedrons and broadband PL properties attributed to strong exciton-phonon coupling.Several studies have synthesized 0D metal halide structures with isolated metal halide octahedral building blocks, and their intrinsic properties have been investigated by tailoring the composition. For example, 0D Cs 4 PbBr 6 perovskites have been extensively studied because of their unique optical properties such as high PLQY, as well as high thermal, chemical, and photostabilities; however, the origin of the green emission of Cs 4 PbBr 6 is still under debate. [20][21][22][23] Lead-free 0D metal halides have also been reported, containing either main group elements, such as tin, [24,25] bismuth, [26] indium, [27] and antimony, [28] or transition metals, such as copper, [29] manganese, [30] and zinc. [31] These metal halides can be utilized as Herein, the synthesis of novel, highly luminescent, and nearly monodisperse zero-dimensional (0D) cesium lanthanide chloride (Cs 3 LnCl 6 ; Ln = Y, Ce, Gd, Er, Tm, Yb) colloidal nanocrystals (NCs) is reported for the first time. The Cs 3 LnCl 6 NCs are synthesized using a heating-up method and exhibit highly uniform size and shape. The monoclinic-phase Cs 3 LnCl 6 NCs contain completely isolated [LnCl 6 ] 3− octahedral units, resulting in 0D ternary metal halide structures. Therefore, these NCs exhibit deep-blue photoluminescence under ultraviolet excitation, and this photoluminescence can be tuned by changing the lanthanide cations within the [LnCl 6 ] 3− octahedral units. High photoluminescence quantum yields of up to 60% and 90% are observed for...

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