A photoconversion efficiency of 1.83 % was observed for a photodevice based on ZnO nanowires sensitized with CdTe quantum dots (QDs; see picture; FTO=F‐doped SnO2), which is more than 200 % greater than that of pristine ZnO nanowires. The presence of CdTe QDs on the surface of ZnO nanowires was confirmed by HRTEM and elemental mapping.

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This investigation demonstrates an environmentally friendly inorganic light-harvesting nanostructure. This system provides a stable photoelectrochemical platform for the photolysis of water. The device is constructed by first building up an array of ZnO nanowires and then incorporating indium phosphide (InP) nanocrystals into them. A different-sized quantum dots (QDs) sensitization of the ZnO nanowire array for splitting water with a substantially enhanced photocurrent was demonstrated. InP QDs of various sizes are utilized as simultaneous sensitizers of the array of ZnO nanowires, and this multi-bandgap sensitization layer of InP QDs can harvest complementary solar light in the visible region while the ZnO nanostructures absorb the UV part of solar light. A photocurrent of 1.2 mA/cm 2 at +1.0 V was observed; it was more than 108% greater than the photocurrent achieved by bare ZnO nanowires. Solar illumination measurements investigated the contribution from photoelectrochemical response and effect in unoccupied states of conduction band. ZnO decorated with single/three-sized InP QDs had a significant increase in photogenerating electrons in 4p orbital, which indicated this increase of photogenerating electrons could be attributable to the absorption of InP QDs in visible region and the photogenerating electrons transfer from conduction band of InP to that of ZnO. The photogenerating electron in conduction band can significantly response to the photoactivity collected in photoelectrochemical measurement, and the contribution of photoresponse from ZnO nanowire or InP quantum dots can be distinguished by comparing the spectra collected under dark/illumination condition.

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Arrays of ZnO nanorods (NRs) were successfully converted into nanotubes (NTs), used as photoelectrodes in photoelectrochemical (PEC) cells after their sensitization with CdSe quantum dots (QDs) and a strong correlation between the PEC performance and geometrical structure of ZnO NTs@CdSe(QDs) and ZnO NRs@CdSe(QDs) was established under the same conditions.

We study the relation between quantum affine algebras of type A and Grassmannian cluster algebras. Hernandez and Leclerc described an isomorphism from the Grothendieck ring of a certain subcategory C ℓ of U q ( sl n )-modules to a quotient of the Grassmannian cluster algebra in which certain frozen variables are set to 1. We explain how this induces an isomorphism between the monoid of dominant monomials, used to parameterize simple modules, and a quotient of the monoid of rectangular semistandard Young tableaux with n rows and with entries in [n + ℓ + 1]. Via the isomorphism, we define an element ch(T ) in a Grassmannian cluster algebra for every rectangular tableau T . By results of Kashiwara, Kim, Oh, and Park, and also of Qin, every Grassmannian cluster monomial is of the form ch(T ) for some T . Using a formula of Arakawa-Suzuki, we give an explicit expression for ch(T ), and also give explicit q-character formulas for finite-dimensional U q ( sl n )-modules. We give a tableau-theoretic rule for performing mutations in Grassmannian cluster algebras. We suggest how our formulas might be used to study reality and primeness of modules, and compatibility of cluster variables.

Natural sensory signals have nonlinear structures dynamically composed of the carrier frequencies and the variation of the amplitude (i.e., envelope). How the human brain processes the envelope information is still poorly understood, largely due to the conventional analysis failing to quantify it directly. Here, we used a recently developed method, Holo-Hilbert spectral analysis, and steady-state visually evoked potential collected using electroencephalography (EEG) recordings to investigate how the human visual system processes the envelope of amplitude-modulated signals, in this case with a 14 Hz carrier and a 2 Hz envelope. The EEG results demonstrated that in addition to the fundamental stimulus frequencies, 4 Hz amplitude modulation residing in 14 Hz carrier and a broad range of carrier frequencies covering from 8 to 32 Hz modulated by 2 Hz amplitude modulation are also found in the two-dimensional frequency spectrum, which have not yet been recognized before. The envelope of the stimulus is also found to dominantly modulate the response to the incoming signal. The findings thus reveal that the electrophysiological response to amplitude-modulated stimuli is more complex than could be revealed by, for example, Fourier analysis. This highlights the dynamics of neural processes in the visual system.

We found that abundant defects could be created in the HC-NiCo-LDH by constructing a hollow nanocage morphology. The HC-NiCo-LDH showed excellent CO2 photoreduction performance that increasing the CH4 selectivity while suppressing the H2 evolution.