Systematic Study of Effective Hydrothermal Synthesis to Fabricate Nb-Incorporated TiO2 for Oxygen Reduction Reaction.

Fuel cells are expected to serve as next-generation energy conversion devices owing to their high energy density, high power, and long life performance. The oxygen reduction reaction (ORR) is important for determining the performance of fuel cells; therefore, using catalysts to promote the ORR is essential for realizing the practical applications of fuel cells. Herein, we propose Nb-incorporated TiO2 as a suitable alternative to conventional Pt-based catalysts, because Nb doping has been reported to improve the conductivity and electron transfer number of TiO2. In addition, Nb-incorporated TiO2 can induce the electrocatalytic activity for the ORR. In this paper, we report the synthesis method for Nb-incorporated TiO2 through a hydrothermal process with and without additional load pressures. The electrocatalytic activity of the synthesized samples for the ORR was also demonstrated. In this process, the samples obtained under various load pressures exceeding the saturated vapor pressure featured a high content of Nb and crystalline TiNb2O7, resulting in an ellipsoidal morphology. X-ray diffraction results also revealed that, on increasing the Nb doping amounts, the diffraction peak of the anatase TiO2 shifted to a lower angle and the full width at half maximum decreased. This implies that the Ti atom is exchanged with the Nb atom during this process, resulting in a decrease in TiO2 crystallinity. At a doping level of 10%, Nb-incorporated TiO2 exhibited the best electrocatalytic activity in terms of the oxygen reduction current (iORR) and onset potential for the ORR (EORR); this suggests that 10% Nb-doped samples have the potential for enhancing electrocatalytic activity.

High mass loading NiCo-OH nanothorns coated CuO nanowire arrays for high-capacity nickel-zinc battery.

The rational design of cathode materials with core-shell heterostructures is significant to develop a Ni//Zn battery with both high gravimetric and areal energy density under high mass loading. In this work, the NiCo-OH nanothorns with a mass loading of 11.6 mg cm-2were coated on CuO nanowire arrays via a chemical bath deposition method. Thanks to the construction of 3D core-shell nanowire arrays and appropriate cobalt doping, as-fabricated Ni//Zn battery based on the NiCo-OH as cathode achieved the maximum specific capacity of 383 mAh g-1at 5 mA cm-2with high energy density of 649 Wh kg-1at 0.73 kW kg-1, indicating good energy storage performance in Ni//Zn battery.

High surface area for La1-xSrxFeO3 (x=0, 0.4, 0.6) as bifunctional catalyst for rechargeable Li-O2 batteries.

Three-dimensionally mesoporous La1-xSrxFeO3 (x = 0, 0.4, 0.6) precursors have been synthesized through a facile solvothermal process. After high-temperature sintering, La1-xSrxFeO3 still exhibits uniform morphology and good dispersibility, which provides a porous structure and favorable surface area. Particularly, La0.4Sr0.6FeO3 shows the biggest surface area of 58 m2 g-1. Doping also induces the generation of oxygen vacancies and Fe4+, which is beneficial for the conductivity and catalytic activity of the materials. Complete with favorable structure and electrochemical activity, La0.4Sr0.6FeO3 exhibits bifunctional catalytic activity in alkaline solution. Applied as a cathode catalyst in Li-O2 batteries, it shows a larger discharge capacity of 23 905 mA h g-1 and a better cycling stability of 100 cycles.

Remarkable enhancement in the electrochemical properties of cosmetic brush-like Co3O4 nanowires via in situ surface modification with Ni2.

Cosmetic brush-like Co3O4 nanowires grown on carbon cloth were prepared by regulating the addition of trisodium citrate by hydrothermal synthesis. Then a simple liquid-phase ion exchange was carried out to improve the electrochemical performance of Co3O4 by surface modification with Ni2+. After surface modification, at a current density of 4 A g-1, the specific capacity significantly increased from 276.1 C g-1 (720.5 F g-1) to 655.9 C g-1 (1525.4 F g-1). Meanwhile, the electrocatalytic oxidation performances of methanol and urea were also improved significantly. The enhanced electrochemical properties were attributed to the modification of the surface of Co3O4 with Ni2+.

Fabrication of carbon cloth supporting MnO x and its application in Li-O2 batteries.

High-efficiency and low-cost electrocatalysts are generally believed to be the critical factor and have been highly researched to catalyze the oxygen reduction reaction (ORR) during the operation of Li-O2 battery (LOB). The catalysts with better ORR performance are essential for high-performance LOBs. Herein, a binder-free MnO x @carbon cloth cathode composed of Mn3O4 nanoparticles and Mn2O3 nanosheets were directly synthesized on the carbon cloth by electrodeposition and subsequently heat treatment at different temperature (from 200 °C to 400 °C). With the increase of temperature, the Mn3O4 nanospheres gradually transformed into Mn2O3 nanosheets. The MnO x obtained at 350 °C exhibited the best ORR performance. And MnO x -350 °C could operate more than 80 cycles at 340 mA g-1 with a limiting specific capacity of 1000 mAh g-1, and its first discharge specific capacity could nearly achieve 8000 mAh g-1 at 200 mA g-1.

Relationship between parental rearing style and emotional and behavioral problems of 3-6-year-old children / 中国学校卫生

Objective@#To understand emotional and behavioral problems of children aged 3-6 years, and to explore the role of parenting style in the development of those problems.@*Methods@#A total of 2 278 children from 11 public kindergartens in Tongling City from April to June 2018 were selected by cluster sampling method. The questionnaire was made up by parents. The questionnaire mainly included: children, basic information of parents and children, children’s psychology and behavior, and parents’ education style, etc.@*Results@#Among 2 278 children, 192(8.43%) had abnormal emotional symptoms, 214 (9.39%) had conduct problems, 376(16.50%) had hyperactivity problems, 537(23.57%) had peer problems, 233(10.2%) had abnormal total difficulty scores and 254(11.15%) had prosocial behaviors. Gender, age, health status of the child, second-hand smoke exposure of the baby, parents’ education level, family economic conditions, and parents’ education mode are all the influencing factors of children’s emotion and behavior(P<0.05). Logistic analysis showed that father’s support participation(OR=0.96, 95%CI=0.95-0.98), mother’s support participation (OR=0.94, 95%CI=0.92-0.95), mother’s hostility compulsion (OR=1.08, 95%CI=1.06-1.10) and 3-6-year-old children’s abnormal mood and behavior were correlated(P<0.01).@*Conclusion@#Parental support and maternal hostile are related to emotional and behavioral problems of 3-6-year-old children.

Simple synthesized Pt/GNs/TiO2 with good mass activity and stability for methanol oxidation.

Pt/GNs/TiO2 (GNs, graphene nanosheets) catalyst was synthesized by a simple two-step method, including a rapid solution plasma technique to obtained Pt nanoparticles with a size of 2-5 nm and followed by an ultrasonic mixing of the Pt, GNs and TiO2 nanoparticles. After coupling with TiO2 nanoparticles, the Pt/GNs/TiO2 catalyst exhibited a promoting catalytic activity towards methanol oxidation, which was superior to the Pt/GNs catalyst. The mass activity of the Pt/GNs/TiO2 catalyst was 3464 mA mgPt-1, which was 3.5 and 3.4 times higher than those of the Pt/GNs and the commercial Pt/C, respectively. And the Pt/GNs/TiO2 showed a strongly negative shift onset potential of methanol oxidation. The results of long-term cyclic voltammetry and CO-stripping tests showed an improved CO tolerance of the Pt/GNs/TiO2. Moreover, the mass activity of the Pt/GNs/TiO2 was further enhanced under light irradiation, with the mass activity of 4715 mA mgPt-1, which was 1.4 times higher than that of in dark. This work provides new opportunities for exploiting efficient visible photo-assisted electro-catalytic methanol oxidation.

[Value of procalcitonin on predicting the severity and prognosis in patients with early ARDS: a prospective observation study].

OBJECTIVE: To investigate the value of procalcitonin (PCT) on predicting the severity and prognosis in patients with early acute respiratory distress syndrome (ARDS). METHODS: A prospective observation study was conducted. A total of 113 patients with ARDS undergoing mechanical ventilation admitted to intensive care unit (ICU) of Affiliated People's Hospital of Jiangsu University from October 2012 to April 2016 were enrolled. Based on oxygenation index (PaO2/FiO2), the patients were classified into mild, moderate, and severe groups according to Berlin Definition. Twenty-five healthy volunteers were served as controls. Demographics, acute physiology and chronic health evaluation II (APACHE II) score, and Murray lung injury score were recorded. Within 24 hours after diagnosis of ARDS, the serum levels of PCT and C-reactive protein (CRP) were determined by enzyme-linked fluorescence analysis (ELFA) and immune turbidimetric method, respectively. The patients were also divided into survival and non-survival groups according to clinical outcome within 28-day follow-up, and the clinical data were compared between the two groups. Spearman rank correlation was applied to determine the correlation between variables. The predictive value of the parameters on 28-day mortality was evaluated with receiver operating characteristic curve (ROC). Kaplan-Meier survival curve analysis was used to compare different PCT levels of patients with 28-day cumulative survival rate. RESULTS: After excluding patients who did not meet the inclusion criteria and loss to follow-up, the final 89 patients were enrolled in the analysis. Among 89 ARDS patients analyzed, 27 of them were mild, 34 moderate, and 28 severe ARDS. No significant differences were found in age and gender between ARDS and healthy control groups. Infection and trauma were the most common etiology of ARDS (55.1% and 34.8%, respectively). Compared with healthy control group, both CRP and PCT in serum of ARDS group were higher [CRP (mg/L): 146.32 (111.31, 168.49) vs. 6.08 (4.47, 7.89), PCT (µg/L): 3.46 (1.98, 5.56) vs. 0.02 (0.01, 0.04), both P < 0.01], and the two showed sustained upward trends with the ARDS course of disease. Compared with mild group, severe group had significantly higher APACHE II and Murray scores. Spearman rank correlation analysis showed that both serum PCT and CRP in patients with ARDS was correlated well with APACHE II score (r values were 0.669 and 0.601, respectively, both P < 0.001), while PCT was weakly but positively correlated with Murray score (r = 0.294, P = 0.005), but not the case of CRP (r = 0.203, P = 0.052). APACHE II score and serum PCT in non-survival group (n = 38) were significantly higher than those of the survival group [n = 51; APACHE II score: 26.00 (23.00, 28.50) vs. 21.00 (17.00, 25.00), PCT (µg/L): 6.38 (2.82, 9.49) vs. 3.09 (1.08, 3.57), both P < 0.01], but Murray score and CRP level were similar between survivors and non-survivors. The areas under ROC curve (AUC) of APACHE II score and PCT for predicting 28-day mortality were 0.781 and 0.793, respectively, which were better than those of AUC of Murray score and CRP (0.606 and 0.561, respectively, all P < 0.05). The AUC of APACHE II score combined with PCT was significantly higher than that of PCT (0.859 vs. 0.793, P = 0.048) or APACHE II score alone (0.859 vs. 0.781, P = 0.038). Using a PCT cut-off value of > 4.35 µg/L for predicting 28-day mortality, the sensitivity and specificity was 92.2% and 63.2%, respectively, and the positive and negative likelihood ratios were 2.50 and 0.12 respectively. Kaplan-Meier survival curve analysis indicated that the patients whose PCT more than 4.35 µg/L, had lower 28-day cummulative survival rate as compared with those with PCT ≤ 4.35 µg/L (log-rank test: χ2 = 5.013, P = 0.025). CONCLUSIONS: The elevated serum PCT level in patients with ARDS seems to be correlated well with the severity of lung injury, and appears to be a useful prognostic marker of outcome in the early phases of ARDS.

Curative and adjunctive AVM Onyx embolization of AVMs through the choroidal arteries.

Objective The anterior or posterior choroidal artery is often recruited to supply deep location arteriovenous malformations (AVMs). This study is to report curative and adjunctive AVM Onyx embolization through these arteries. Methods This study retrospectively reviewed six patients with cerebral AVMs who underwent endovascular embolization through the choroidal arteries between October 2015 and October 2016. Embolization was performed as a curative procedure in five patients and adjunctive procedure in one patient. Results Four patients underwent embolization through the anterior choroidal artery (AchA), and two patients underwent embolization through the lateral posterior choroidal artery (LPchA). One of the four patients in whom embolization was from the AchA (distal to the plexal point) developed transient hemiparesis. Complete obliteration was confirmed by angiography at the last follow-up in five patients. Conclusions Onyx embolization of cerebral AVMs through the choroidal arteries is possible as a curative or adjunctive procedure.

Facile Fabrication of Platinum-Cobalt Alloy Nanoparticles with Enhanced Electrocatalytic Activity for a Methanol Oxidation Reaction.

Decreasing the cost associated with platinum-based catalysts along with improving their catalytic properties is a major challenge for commercial direct methanol fuel cells. In this work, a simple and facile strategy was developed for the more efficient preparation of multi-walled carbon nanotube (MWCNT) -supported Pt/CoPt composite nanoparticles (NPs) via solution plasma sputtering with subsequent thermal annealing. Quite different from general wet synthesis methods, Pt/CoPt composite NPs were directly derived from metal wire electrodes without any additions. The obtained Pt/CoPt/MWCNTs composite catalysts exhibited tremendous improvement in the electro-oxidation of methanol in acidic media with mass activities of 1719 mA mg-1Pt. This value is much higher than that of previous reports of Pt-Co alloy and commercial Pt/C (3.16 times) because of the many active sites and clean surface of the catalysts. The catalysts showed good stability due to the special synergistic effects of the CoPt alloy. Pt/CoPt/MWCNTs can be used as a promising catalyst for direct methanol fuel cells. In addition, this solution plasma sputtering-assisted synthesis method introduces a general and feasible route for the synthesis of binary alloys.

Synthesis and photocatalytic activity of Pt-ZnO hybrid nanocomposite by solution plasma technology.

In this paper, Pt-ZnO hybrid nanocomposites were prepared by solution plasma technology. X-ray diffraction (XRD) and energy dispersive x-ray analysis (EDX) were used to verify their chemical composition. The size and morphology of the Pt-ZnO hybrid nanocomposites were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These results indicate that about 2-3 nm Pt nanoparticles (NPs) were synthesized and dispersed on the pyramid-like ZnO (20-60 nm) surface. Photodegradation of Rhodamine B (RhB) demonstrates that the Pt (5 wt%)-ZnO hybrid nanocomposite has better photocatalytic activity than commercial P25 because Pt NPs restrain the photogenerated electron/hole recombination and increase the catalyst activity.

In-situ one-step synthesis of carbon-encapsulated naked magnetic metal nanoparticles conducted without additional reductants and agents.

C-encapsulated highly pure Ni, Co, and Fe magnetic nanoparticles (MNPs/C) were synthesized by an innovative one-step in-situ plasma in liquid method (solution plasma processing, SPP) without any additional reductants, agents, or treatment. Successful encapsulation of MNPs was demonstrated by using inductively coupled plasma-atomic emission spectrometry and cyclic voltammetry techniques. The obtained X-ray diffraction patterns and transmission electron microscopy images corresponded to MNPs with average diameters of 5 nm and good crystalline structure. The C capsules with spherical shapes (containing onion-like layers) were characterized by uniform sizes (ranging from 20 nm to 30 nm) and chain-like morphologies. The synthesized MNPs/C exhibited superparamagnetic properties at room temperature and might be utilized in data storage, biomedical, and energy applications since various NPs (including bimetallic ones) could be easily prepared by changing working electrodes. This study shows the potential of SPP to be a candidate for the next-generation synthesis method of NPs/C.

Chitosan/titanium dioxide nanocomposite coatings: Rheological behavior and surface application to cellulosic paper.

Incorporation of nanofillers into a polymeric matrix has received much attention as a route to reinforced polymer nanocomposites. In the present work, an environmentally friendly chitosan (CTS)/titanium dioxide (TiO2) nanocomposite coating was designed/prepared and subsequently employed for imparting antibacterium and improved mechanical properties to cellulosic paper via surface coating. Effect of TiO2 nanoparticle loadings on the rheological behavior of nanocomposite coatings was investigated. Surface application of CTS/TiO2 nanocomposite coatings to cellulosic paper was performed, and the antibacterial activity and mechanical properties of surface-coated cellulosic paper were examined. Results showed that the increased TiO2 nanoparticle loadings decreased the viscosity and dynamic viscoelasticity of the as-prepared coatings, and improved the antibacterial activity and mechanical properties of surface-coated cellulosic paper. The optimum loading of TiO2 nanoparticles was identified at 10%. This work suggested that CTS/TiO2 nanocomposite coatings may have the potential to be used as a promising antibacterial protective coating for paper packaging.

The influence of age and the initial clinical presentations of patients with an arteriovenous malformation on the risk of hemorrhage.

BACKGROUND AND PURPOSE: The major determinants of hemorrhage in an arteriovenous malformation (AVM) include its angioarchitecture, as well as the patient's age and clinical presentation. The aim of this study was to determine whether or not the risk of hemorrhage in an AVM differs based on the different clinical presentations and the initial age at diagnosis. METHODS: A consecutive case series of 496 patients having a brain AVM was retrospectively analyzed. The radiological evidence of hemorrhage was established in 84 of these cases after the initial diagnosis of AVM had been made. These cases were analyzed using univariate analysis and Kaplan-Meier curves with respect to age at diagnosis, the clinical presentation of patients harboring the AVM as well as the Spetzler-Martin grade of the AVM. RESULTS: Hemorrage occurred in 84 patients with an AVM during a mean duration of 2.5 years (range, 1month-28 years). In univariate analysis, a subsequent hemorrhage within an AVM was associated with the following factors: When the patients initially presented with a hemorrhage, and, had a younger age (<30 years), female gender, and Spetzler-Martin III and IV grades. By analysis of the Kaplan-Meier curves, it was estimated that the annual hemorrhage rate was 12.3% in those cases who initially presented with hemorrhage, compared with 3.5% for those cases whose initial presentation was not associated with AVM bleed. In the latter category (i.e., patients who did not have hemorrhage as the initial presentation), the annual rate of subsequent hemorrhage was lower for those patients who initially presented with seizures than those who had other initial presentations (such as those having neurological deficits, headaches, or those incidentally detected to be having an AVM) (with the bleeding rate being 1.9% in those with seizures as the initial presentation vs. 4.6% for the other presentations or those with incidentally detected AVMs, P = 0.002). CONCLUSIONS: The subsequent occurrence of hemorrhage in an AVM was associated with the initial presentation of hemorrhage, a younger patient's age (<30 years), the female gender, and Spetzler-Martin grades III and IV. The risk of subsequent hemorrhage in patients with an initial presentation of a seizure was lower than the risk of hemorrhage that occurred with other presentations. Patients with an AVM who present with recurrent headaches, and those in whom the AVM has been detected incidentally, should also be kept under surveillance as they too manifest a risk of a subsequent hemorrhage.

Effect of Microwave Treatment of Graphite on the Electrical Conductivity and Electrochemical Properties of Polyaniline/Graphene Oxide Composites.

Polyaniline (PANI)/graphene oxide (GO) composites were synthesized via in situ polymerization of aniline in the presence of GO. The effect of microwave treatment of graphite on the electrical conductivity and electrochemical properties of PANI/GO composites was highlighted, and the morphology and microstructure were subsequently characterized using transmission electron microscopy, scanning electron microscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. The results demonstrated that microwave treatment of graphite imparted a well-dispersed, highly ordered layered structure to the as-prepared GO, and in turn facilitated strong bonding between the GO and PANI nanosheets, which may be responsible for the improved electrical conductivity and electrochemical properties of the resulting PANI/GO composites. The desired PANI/GO composites possessed an electrical conductivity of 508 S/m, an areal capacitance of 172.8 mF/cm², and a retained capacitance of 87.4% after cycling, representing percentage increases of 102, 232, and 112, respectively, as a result of the microwave treatment of graphite. The resulting composites are promising electrode materials for high-performance and ecofriendly electrical energy storage devices.

Patient Age, Hemorrhage Patterns, and Outcomes of Arteriovenous Malformation.

BACKGROUND: The angioarchitecture and presentation of arteriovenous malformations (AVMs) associated with AVM hemorrhage may vary with patient age. Our aim was to determine the influence of patient age at diagnosis on hemorrhage patterns and outcomes. METHODS: A consecutive case series of 267 cases of ruptured AVMs was retrospectively analyzed. Hemorrhage patterns (intracerebral hemorrhage, subarachnoid hemorrhage, and intraventricular hemorrhage) were confirmed based on computed tomography imaging at initial diagnosis. Clinical outcomes were classified with a modified Rankin Score. These cases were analyzed with respect to age at diagnosis, hemorrhage patterns, Spetzler-Martin grades, and their clinical outcomes. RESULTS: During a mean 22.2 months follow-up time (range, 7 hours to 10 years), 212 cases (79.4%) were favorable (modified Rankin Score ≤2) and 55 cases (21.6%) were unfavorable (modified Rankin Score ≥3). The mean age was higher in patients with an unfavorable outcome at follow-up. In univariate analyses, different age groups were significantly associated with bleeding patterns (P = 0.022). Unfavorable outcome was associated with intracerebral hemorrhage (odds ratio, 0.330; 95% confidence interval, 0.142-0.768; P = 0.008) and evacuation of hematoma (odds ratio, 0.195; 95% confidence interval, 0.044-0.867; P = 0.025), whereas intraventricular hemorrhage, subarachnoid hemorrhage, and intraventricular drainage were significantly associated with a favorable outcome. Different age groups were not significantly associated with bleeding patterns, sex, and the location of the AVM, and Spetzler-Martin grades did not show a significant association with the severity of outcomes. CONCLUSIONS: Different age groups were significantly associated with bleeding patterns. Higher patient age, intracerebral hemorrhage, and evacuation of hematoma seem to be associated with an unfavorable outcome after AVM rupture.

[Effect of continuous renal replacement therapy started at different time on patients with multiple organ dysfunction syndrome].

OBJECTIVE: To explore the effects of continuous renal replacement therapy (CRRT) on serum cytokines and prognosis in multiple organ dysfunction syndrome (MODS) patients based on different therapeutic opportunities. METHODS: A total of 34 MODS patients in the treatment of CRRT after admission to ICU of our hospital between July 2008 and October 2010 were recruited. Based on the time interval from the onset of MODS to the initiation of CRRT, the patients were stratified into early group (0 - 3 days, n = 16) and late group (4 - 10 days, n = 18). Both groups of MODS patients received conventional treatment in addition to 72 hours of high-volume hemofiltration (HVHF). The serum levels of such inflammatory mediators as interleukin (IL)-1ß, interleukin-1 receptor antagonist (IL-1Ra), IL-6, tumor necrosis factor (TNF)-α, soluble tumor necrosis factor receptor1 (sTNFR1) and IL-10 were detected by enzyme linked immunosorbent assay (ELISA) before CRRT (0 h) and 6, 12, 18, 24, 48 and 72 h during the treatment of CRRT. Dynamic APACHEII scores were also evaluated. RESULTS: (1) The early group had lower serum levels of IL-1ß, IL-6, IL-10 and higher IL-1Ra, L-1Ra/IL-1ß ratio at 72 h than those of 0 h (P < 0.05). And the late group had a declining serum level of IL-1ß, IL-6, TNF-α and IL-10 and a rising ratio of IL-1Ra and IL-1Ra/IL-1ß during the first 24 h (P < 0.05). As compared with the late group, the early group had a lower level of IL-10 [(25 ± 12) vs (51 ± 33) ng/L] and higher ratios of IL-1Ra and IL-1Ra/IL-1ß at 72 h [(1382 ± 899 vs (683 ± 188) ng/L, (54 ± 10) vs (23 ± 6)] (both P < 0.05). (2) The early group had a lower APACHEIIscore than the late group at 0 h (P < 0.05). APACHEII score at 72 h was significantly lower than 0 h in the early group. And there was no obvious change in the late group. There was no statistical difference in the numbers of MODS patients with dysfunctional organs number ≥ 4 at 0 h in both groups. The number of MODS patients with dysfunctional organs number ≥ 4 at 72 h was lower than 0 h in the early group (P < 0.05). And there was no statistical difference in the late group. CONCLUSION: Regulating the ratio of anti-inflammatory/pro-inflammatory mediators is critical in the immunomodulation of CRRT. And CRRT may provide more clinical benefits in the early phase (0 - 3 days) of MODS.

Low-temperature fabrication of bunch-shaped ZnO nanowires using a sodium hydroxide aqueous solution.

Bunch-shaped ZnO nanowires film was successfully fabricated by the forced-hydrolysis-initiated-nucleation of anhydrous zinc acetate in an aqueous solution of zinc acetate and sodium hydroxide at low temperature. X-ray diffraction and a field emission scanning electron microscope clarified their formation mechanism and morphology development. The morphology was controllable by adjusting the solution temperature and deposition time. ZnO nanowires obtained at 65 degrees C for 6 h have a high aspect ratio of about 106. The smaller diameter with higher aspect ratio of ZnO nanowires, the easier the formation of bunch shapes by the capillary force during the drying process. This fabrication technique indicated that bunched ZnO film was prepared at low cost, and fittable to low heat-resistance substrates such as a polymer substarte.

Micropatterning of ZnO nanoarrays by forced hydrolysis of anhydrous zinc acetate.

Micropatterns of ZnO nanoarrays were simply and successfully fabricated in an aqueous solution without any high-temperature treatment and/or expensive catalyst. In situ forced hydrolysis of patterned anhydrous zinc acetate, derived by ultraviolet irradiation with a photomask, resulted in heterogeneous nucleation and growth to form ZnO nanoarrays. Micropatterns of ZnO nanoarrays were characterized by FE-SEM and XRD. ZnO nanoarrays were well site-selectively deposited on anhydrous zinc acetate coated regions at 88 degrees C. HR-TEM clarified the formation mechanism in which anhydrous zinc acetate showed a tendency of forced hydrolyzation to ZnO nanocrystals at the initial stage in the reaction solution.

In situ forced hydrolysis-assisted fabrication and photo-induced electrical property in sensor of ZnO nanoarrays.

ZnO nanowhiskers are successfully fabricated on an anhydrous zinc acetate coated substrate by its in situ forced hydrolysis at the initial stage without pre-existing ZnO seeds or catalyst. HR-TEM clarified the formation mechanism that in situ forced hydrolysis of an anhydrous zinc acetate layer to ZnO nanocrystals at the initial stage promoted growth of ZnO nanowhiskers by heterogeneous nucleation and growth. ZnO nanowhiskers films show high transmittance over 80% in the visible range and bandgap energy of 3.29 eV. Porous semiconductor ZnO films show good photo-induced electrical properties after various concentrations of DNA molecules labeled with photoactive dye molecules were adsorbed. In situ forced hydrolysis-assisted technique at low temperature can be useful for the fabrication of optoelectronic devices with low cost and without using expensive catalyst.