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Photocatalysis has been regarded as a promising strategy for hydrogen production and high-value-added chemicals synthesis, in which the activity of photocatalyst depends significantly on their electronic structures, however the effect of electron spin polarization has been rarely considered. Here we report a controllable method to manipulate its electron spin polarization by tuning the concentration of Ti vacancies. The characterizations confirm the emergence of spatial spin polarization among Ti-defected TiO 2 , which promotes the efficiency of charge separation and surface reaction via the parallel alignment of electron spin orientation. Specifically, Ti 0.936 O 2 , possessing intensive spin polarization, performs 20-fold increased photocatalytic hydrogen evolution and 8-fold increased phenol photodegradation rates, compared with stoichiometric TiO 2 . Notably, we further observed the positive effect of external magnetic fields on photocatalytic activity of spin-polarized TiO 2 , attributed to the enhanced electron-spin parallel alignment. This work may create the opportunity for tailoring the spin-dependent electronic structures in metal oxides.

Bismuth vanadate photoanode has shown great potential for photoelectrochemical (PEC) catalysis, but it needs to be further modified because of its relatively low charge-separation efficiency and poor stability. Herein, the bimetallic phosphide NiCoP decorated Mo-BiVO 4 is fabricated through the electrodeposition and drop-casting method, which significantly improves the charge separation and surface oxidation reaction. Therefore, the fabricated NiCoP/Mo-BiVO 4 photoanode exhibits a low onset potential of 0.21 V ( vs. RHE) and high photocurrent of 3.21 mA cm -2 at 1.23 V ( vs. RHE), which is 3.12 times higher than that of pure BiVO 4 . Importantly, the decoration of NiCoP significantly improve the stability of BiVO 4 photoanode., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

The utilization of solar energy in photoelectrochemical water splitting is a popular approach to store solar energy and minimize the dependence on fossil fuels. Herein, defected ZnWO 4 -decorated WO 3 nanorod arrays with type II heterojunction structures were synthesized via a two-step solvothermal method. By controlling the amount of Zn precursor, WO 3 nanorods were decorated in situ with tunable amounts of ZnWO 4 nanoparticles. Characterization confirmed the presence of abundant W 5+ species in the defected ZnWO 4 -decorated WO 3 samples, leading to enhanced light absorption and charge-separation efficiency. Therefore, the decorated WO 3 nanorod arrays show much higher photoelectrochemical (PEC) activity than pure WO 3 nanorod arrays. Specifically, the sample with optimal ZnWO 4 decoration and surface defects exhibits a current density of 1.87 mA cm -2 in water splitting at 1.23 V vs. RHE under 1 sun irradiation (almost 2.36 times higher than that of pure WO 3 ), a high incident photon-to-current efficiency of nearly 40% at 350 nm, and a relatively high photostability. However, the decoration of WO 3 with too much ZnWO 4 blocks the light absorption of WO 3 , inhibiting the PEC performance, even when many defects are present. This work provides a promising approach to rationally construct defected heterojunctions as highly active PEC anodes for practical applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Photo-electrochemical (PEC) water splitting, as an essential and indispensable research branch of solar energy applications, has achieved increasing attention in the past decades. Between the two photoelectrodes, the photoanodes for PEC water oxidation are mostly studied for the facile selection of n-type semiconductors. Initially, the efficiency of the PEC process is rather limited, which mainly results from the existing drawbacks of photoanodes such as instability and serious charge-carrier recombination. To improve PEC performances, researchers gradually focus on exploring many strategies, among which engineering photoelectrodes with suitable cocatalysts is one of the most feasible and promising methods to lower reaction obstacles and boost PEC water splitting ability. Here, the basic principles, modules of the PEC system, evaluation parameters in PEC water oxidation reactions occurring on the surface of photoanodes, and the basic functions of cocatalysts on the promotion of PEC performance are demonstrated. Then, the key progress of cocatalyst design and construction applied to photoanodes for PEC oxygen evolution is emphatically introduced and the influences of different kinds of water oxidation cocatalysts are elucidated in detail. Finally, the outlook of highly active cocatalysts for the photosynthesis process is also included.

Mesoporous hollow W18O49 spheres were fabricated by a facile solvent-induced assembly method using anhydrous WCl6 as a precursor and CH3COOH as a solvent. This unique structure exhibited remarkably enhanced photocatalytic and photoelectrocatalytic performance than other morphologies like urchin and nanowire due to the simultaneous enhancement in light harvesting, surface area and adsorption capability.

Top-down nanostructure engineering and band engineering are promising methods for fabricating efficient photocatalysts with enhanced optical and electronic properties; however, composites with simultaneously engineered structure and band are very rare. Herein, we constructed a unique architecture composed of a W18O49 nanowire alignment core and porous BiOCl shell (WA@BiOCl), which combined the advantages of both an assembly structure and a type II core-shell heterojunction. The W18O49 alignments (WA) were synthesized using a "one-pot" solvothermal treatment of WCl6/NaNO3via NO3(-)-mediated assembly, whereas the W18O49 nanowires with BiOCl shell (W@BiOCl) were obtained using WCl6/BiCl3. Then, WA@BiOCl, in contrast to W@BiOCl alignments, were fabricated when WCl6 and Bi(NO3)3 were present in the starting mixture. Optical absorption, photoelectrochemical measurements and photoluminescence characterizations show that either the alignments or the core-shell heterojunctions can enhance light harvesting, photo-charge transfer and collection. As a synergetic result, the WA@BiOCl architecture exhibited very high photoactivity and photostability. Under UV-vis (or vis) irradiation, WA@BiOCl is 2.43 (1.93), 3.93 (2.73) and 5.34 (3.44)-fold more active than W@BiOCl, WA and W18O49, respectively. The results demonstrate that the simultaneous nanostructure and band engineering can produce a more efficient photocatalyst than a single strategy alone, which suggests a potential method for the fabrication of photocatalysts in the fields of environment and energy.

V-doped TiO2 quantum dots (QDs) possessing many Ti(3+) defects were fabricated by simple hydrolysis using MCM-41 as a support. The QDs show high charge-separation efficiency and high photocatalytic activity due to the quantum size effect and the newly formed defect- and dopant-mediated band levels.

Objective: To investigate the treatment of upper lip atrophy resulted by previous therapy., Methods: From Mar. 2008 to Mar. 2012, 4 cases with upper lip atrophy resulted by radiotherapy and sclerosing agent injection were treated with lower orbicularis oris muscle flap wrapped by acellular dermis. The thickness and height of upper lip were increased to improve the lip atrophy., Results: Primary wound healing was achieved in all the 4 cases. All the patients were followed up for 3 years with obvious improvement and inconspicuous scar., Conclusion: The volume of lower lip in children is not sufficient as donor site. The lower orbicularis oris muscle flap wrapped by acellular dermis can effectively improve the lip thickness and vermilion portion of upper lip.

Objective: To discuss the segmental monobloc osteotomy and bi-directional distraction for the treatment of Crouzon syndrome in an infant., Methods: A 9-month-old female infant underwent monobloc osteotomy through combined intra- and extra-cranial way. The facial skull was divided into frontal, orbital and maxillary segments. The external distractor was used to move the frontal segment, orbital segment and midface forward. The internal distractor was used to move the maxilla downward. The consolidation lasted for 3 months after distraction., Results: The osteotomy and distraction were successfully completed. The distraction distance reached 18 mm, showing by distractor. The real distraction distance of facial bone was 12 mm, documented by 3-D image. The skull deformity and severe depression of midface improved a lot. The exophthalmos and underbite were corrected. The obstructive sleep apnea also improved markedly. However, the downward movement of maxilla was limited., Conclusions: Monobloc osteotomy with external distractor, as well as maxillary distraction, could be used for Crouzon syndrome in infant. It is safe and effective method which can be performed in an early age for Crouzon syndrome with obstructive sleep apnea.

Mechanism about the change of GaAs phtotocathode's surface barrier during Cs activated process was studied. Ionized Cs and p type doping impurity(Be) form a dipole that decreases the vacuum level of GaAs. Generally, Cs activated GaAs photocathode could achieve zero electron affinity state. The quantum yield formula of reflection-mode photocathode has been solved from the 1-dimension continuity equations and the escape probability formula has been solved from the Schrodinger equation. It was found from the formula that the quantum efficiency of Cs activated GaAs photocathode is directly proportional to the electric field intensity of Be- -Cs+ dipole. A Cs activation experiment was carried out, the experiment process tallies with the theory mentioned above and the integral sensitivity of Cs activated GaAs photocathode is 453 microA x lm(-1), which could be inferred as a zero electron affinity state.

Objective: To discuss the diagnosis and treatment of children sinus pericranii (SP)., Methods: From Jan. 2000 to Dec. 2008, 12 cases of SP were treated. The clinical data and CT results were studied. If the SP had no communication with the intracranial vessels, DSA was performed to know its venous drainage. The operation procedures included excision of bump, followed by hemostasis. Then the local flap was used to cover the cranial defect., Results: 12 cases all had scalp bump whose size was changed with body position. Three-dimensional CT showed a crater-like depression and multiple honeycomb diploic holes in the skull. 6 cases with venous malformation received DSA. 12 patients were operated., Conclusions: SP can be diagnosed with typical CT results and symptoms. DSA should be performed if the communication with the intracranial vessels is existed. The main methods include operation, embolization and reserved observation. Medicine injection is not recommended due to the high risk.

Objective: To investigate the management of congenital scalp defects in infants., Methods: From 1996 to 2008, 6 infants with congenital scalp defects were treated with dressing change, flap transposition, or tissue expansion combined with skull defect reconstruction., Results: Parietal scalp defects in 6 cases were healed after treatment. 5 cases were followed up for 3 months to one year. 2 cases had scalp alopecia in some areas. The scar was inconspicuous in the other 3 cases., Conclusions: Dressing change is suitable for small scalp defect, while flap transposition should be used for medium defect. For large full-thickness cranial defect, dressing change and tissue expansion should be performed at the first stage, followed by skull defect reconstruction and expanded flap transposition.

Objective: To investigate the feasibility of mandibular distraction osteogenesis (MDO) in the treatment of airway obstruction in Pierre Robin syndrome (PRS)., Methods: From 2007 to 2009, 8 newborns with PRS were treated with MDO. The mandibular distractors were fixed after bilateral oblique mandibular osteotomy. The distraction was started one day after operation, three times a day. The distraction distance was 1.2 mm per day until it reached about 12 -20 mm (mean 15 mm)., Results: The distraction was successfully completed in 8 cases with no complication. The distraction distance reached 15 mm, as we expected. The discontinuity cyanosis, inspiratory dyspnea, dystithia were improved after distraction., Conclusions: MDO is feasible and safe for the treatment of airway obstruction in PRS.

NiO-loaded semiconductors have been extensively used as the photocatalysts for water splitting. The metal-support interface is an important factor affecting the efficiency. In the present work, the pretreatment methods were studied to produce a more desirable metal-support interface using Ta2O5 and ZrO2 as the support. The traditional method includes a thermal decomposition, reduction at 773 K, and oxidation at 473 K (R773-O473). The thermal decomposition of Ni(NO3)2 makes the Ni atoms migrate into the bulk of the supports, resulting in a diffused interfacial region. Alternatively, a cold plasma treatment was used to replace the thermal decomposition. Metal salts are quickly decomposed by glow discharge plasma treatment at room temperature, avoiding the thermal diffusion of Ni atoms. With the sequent R773-O473 treatment, a clean metal-support interface is produced. Moreover, the metal particles have optimal shapes with a larger surface. In photocatalysis, the clean metal-support interface is more favorable for the charge separation and transfer, and the increased metal surface provides more active sites. NiO/Ta2O5 and NiO/ZrO2 prepared with the plasma treatment exhibit higher activity for photocatalytic hydrogen generation from pure water and methanol solution, respectively. This work shows the potential of cold plasma treatment in the preparation of metal-loaded catalysts and nanostructured materials.