Construction of nickel-doped cobalt hydroxides hexagonal nanoplates for advanced oxygen evolution electrocatalysis.

Oxygen vacancy of the catalyst is one of the most significant factors affecting the oxygen evolution reaction (OER) electrocatalysis, a key process for overall water splitting. Here, we report the oxygen vacancy engineering of Co(OH)2 hexagonal nanoplates by doping Ni element, which can efficiently lower the average Co oxidation state and thus optimize the Gibbs free energy of the intermediates, giving rise to the largely promoted OER performances. Impressively, the as-obtained oxygen-vacancy-rich Ni-doped Co(OH)2 hexagonal nanoplates manifest OER overpotential as low as 238 mV at 10 mA cm-2 in 1 M KOH solution, being superior to most of binary CoNi hydroxides. In accordance with the high OER activity, it also displays excellent durability in strong alkaline media over 40 h, presenting an advanced electrocatalyst for OER.

Age-specific Mycoplasma pneumoniae pneumonia-associated myocardial damage in children.

OBJECTIVE: To measure Mycoplasma pneumoniae pneumonia (MPP)-associated myocardial damage in different age groups of children with pneumonia. METHODS: Children aged 0-14 years with pneumonia and myocardial damage (serum creatine kinase isoenzyme-MB [CK-MB] concentration >25 U/l) were enrolled in the study. The children were classified as Mycoplasma pneumoniae immunoglobulin M positive (M. pneumoniae IgM+) or negative (M. pneumoniae IgM-) based on a serological test. Children were stratified into four age groups in order to analyse age-specific MPP-associated myocardial damage. RESULTS: The incidence of fever was significantly higher in children who were M. pneumoniae IgM+ compared with M. pneumoniae IgM- children. The median serum CK-MB concentration was significantly higher in children who were M. pneumoniae IgM+ compared with those who were M. pneumoniae IgM-. Children who were M. pneumoniae IgM+ in the 13-36 months and 72 months-14 years age groups had significantly higher median serum CK-MB concentrations than those who were M. pneumoniae IgM- in the same age group. CONCLUSIONS: M. pneumoniae infection was associated with greater myocardial damage in children aged 13-36 months and 72 months-14 years. This suggests age-specific immune responses to M. pneumoniae.

Highly efficient fibrous dye-sensitized solar cells based on TiO2 nanotube arrays.

The structure of fibrous dye-sensitized solar cells, which were constructed by a TiO(2) nanotube array on Ti wire as the photoanode twisted by a Pt wire counter electrode, has been first systematically investigated by accurately controlling the thread pitch distance of screwed Pt wire. It has been revealed that the thread pitch will strongly influence the photovoltaic performance and kinetic processes in fibrous solar cells. The effect of the length of the TiO(2) nanotube on cell performance has also been discussed. After optimization, a relatively universal optimized thread pitch value of 1 mm for fibrous DSCs has been proved and the light-to-electricity conversion efficiency has been remarkably improved to 5.84%.

Note: a high performance pulse energy detector for Q-switched laser based on photoacoustic effect.

A high performance pulse energy detector is developed based on photoacoustic effect. Different from the detectors reported before which also utilized photoacoustic effect, our detector can measure the energy of each pulse output from a Q-switched laser and monitor the pulse energy fluctuation in real time owing to the signal processing circuit designed. By comparing with a commercial laser energy meter, our detector is proved to be of high sensitivity and accuracy. We test the detector under illumination of different pulse energy at varied wavelengths, and the results demonstrate that the detector has a broad spectral response and a dynamical energy range. Besides, the measurements of this detector will not be affected by the background light according to the principle of photoacoustic effect.

Highly efficient CdS/CdSe-sensitized solar cells controlled by the structural properties of compact porous TiO2 photoelectrodes.

At present, the photovoltaic performance of quantum dot-sensitized solar cells (QDSCs) is still much lower than conventional DSCs. Appropriate porous TiO(2) photoanodes for QDSCs need to be further investigated, and optimization of the nanoparticle-based photoanodes is highly desirable as well. In this article, the influence of the structural properties of various TiO(2) photoanodes on CdS/CdSe-sensitized solar cells have been systematically studied. Quantitative analyses of light-harvesting efficiency (LHE) and electron-transfer yield (Φ(ET)) for the QDSCs are investigated for the first time. It is revealed that the LHE increases in the long wavelength region with the addition of large size TiO(2) particles to the transparent film. In the meantime, the balance between the light scattering and surface area also needs to be controlled, which can significantly restrain the dark current of the device. A double-layer photoanodic structure can give 4.92% of light-to-electricity conversion efficiency with a photoactive area of 0.15 cm(2).

A flexible photoelectrode for CdS/CdSe quantum dot-sensitized solar cells (QDSSCs).

We, for the first time, prepared a flexible photoelectrode for CdS/CdSe quantum dot-sensitized solar cells (QDSSCs). A power conversion efficiency of 3.47% was achieved under AM 1.5G illumination for a sandwich type QDSSC consisting of this flexible photoelectrode, Cu(2)S counter electrode and polysulfide electrolyte between the electrodes.

Study on the effect of measuring methods on incident photon-to-electron conversion efficiency of dye-sensitized solar cells by home-made setup.

An experimental setup is built for the measurement of monochromatic incident photon-to-electron conversion efficiency (IPCE) of solar cells. With this setup, three kinds of IPCE measuring methods as well as the convenient switching between them are achieved. The setup can also measure the response time and waveform of the short-circuit current of solar cell. Using this setup, IPCE results of dye-sensitized solar cells (DSCs) are determined and compared under different illumination conditions with each method. It is found that the IPCE values measured by AC method involving the lock-in technique are sincerely influenced by modulation frequency and bias illumination. Measurements of the response time and waveform of short-circuit current have revealed that this effect can be explained by the slow response of DSCs. To get accurate IPCE values by this method, the measurement should be carried out with a low modulation frequency and under bias illumination. The IPCE values measured by DC method under the bias light illumination will be disturbed since the short-circuit current increased with time continuously due to the temperature rise of DSC. Therefore, temperature control of DSC is considered necessary for IPCE measurement especially in DC method with bias light illumination. Additionally, high bias light intensity (>2 sun) is found to decrease the IPCE values due to the ion transport limitation of the electrolyte.

Fibrous CdS/CdSe quantum dot co-sensitized solar cells based on ordered TiO2 nanotube arrays.

A new kind of fibrous quantum dot sensitized solar cell has been designed and fabricated by using CdS and CdSe co-sensitized TiO(2) nanotubes on Ti wire as the photoanode and highly active Cu(2)S as the counter electrode. By optimizing the CdSe deposition time and the length of the nanotube, a power conversion efficiency of 3.18% has been obtained under AM 1.5 illumination (100 mW cm(-2)). The potential application of this kind of solar cell has also been discussed in this paper.