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In this study, Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst was synthesized by in-situ photo-reducing of silver on S,N-TiO2-x nanocomposite and used to degrade bisphenol A (BPA) through heterogeneous activation of potassium peroxymonosulfate (PMS) under visible-light illumination. The structure, physicochemical property, morphology, and electronic property were evalutated by X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectra (XPS), high-resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectra (UV-vis DRS), electron paramagnetic resonance (EPR) spectrum. Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst exhibited 2.4 times higher activity for the synergetic degradation of BPA than that of its counterpart, and 48.73% mineralization rate of BPA also achieved. It was ascribed to the uniformly-dispersed metallic Ag atoms as the active site for accelerating the migration rate of photo-generated carrier for generation of high reactive radicals. The EPR experiments indicated that SO4•‒ and •OH was jointly involved in BPA degradation.

Aging population has been boosting the need for orthopedic implants. However, biofilm has been a major obstacle for orthopedic implants due to its insensitivity to antibiotics and tendency to drive antimicrobial resistance. Herein, an antibacterial polypeptide coating with excellent in vivo adhesive capacity was prepared to prevent implants from forming biofilms and inducing acquired antibiotic resistance. A peptide-based copolymer, poly[phenylalanine

Controlling the compositions and morphologies of the electrocatalysts were conventionally used for improving the catalytic activities. Here, visible-light-enhanced electrocatalytic water reduction reactions on semimetal bismuth (Bi) nanorods were achieved. The Bi catalyst not only exhibited an ideal Faradaic efficiency of 98% for electrocatalytic hydrogen production, but also acted as a light absorber for improving the activity even under light irradiation up to 740 nm. As a result, the solar-to‑hydrogen conversion efficiency under simulated AM 1.5G illumination was reached to 0.82%, which is 2.7 times higher than that induced by plasmon Au nanoparticles. This conversion efficiency is attributed to the excellent solar light absorption property of Bi and the enhanced electron-transfer at the interface of Bi/electrolyte under irradiation. The low-cost Bi catalyst with the dual function could open a venue toward designing more-energy-efficient electrocatalysts for hydrogen production assisted by sunlight.

Graphitic carbon nitride (g-C3N4) with Pt co-catalyst was synthesized by in-situ photoreduction and used as a visible light photocatalyst. The size of Pt co-catalyst can be controlled form single atoms to nano-clusters by the induced amount of Pt precursor. The results indicated that compared with nano-clusters, the Pt0.1-CN (with 0.1 wt% Pt loading amount) which is characterized as single-atom Pt exhibits a pronounced photocatalytic hydrogen evolution capability. For Pt0.1-CN with single-atom Pt as co-catalyst, the H2 generation is up to 473.82 µmol mg−1pt under visible light irradiation (λ > 420 nm). The enhanced photocatalytic performance is mainly attributed to the synergistic effect of high light adsorption efficiency, effective charge separation, and high dispersed active sites of Pt atoms. The results of this work highlighted that loading g-C3N4 with Pt single atoms will achieve a maximum utilization efficiency of Pt atoms and an improvement photocatalytic performance.

Removal of triclosan (TCS) in water has attracted increasing attention due to its high detection frequency and potential toxicity. In this study, porous TiO2 nanotube arrays (TiO2 NTA) was prepared as the reactive electrochemical membrane (REM) to adsorb aqueous TCS, and subsequently to degrade TCS in-situ (a regeneration process of TiO2 NTA). Adsorption kinetics and thermodynamic of TCS followed pseudo-second-order model and Langmuir model, respectively. Compared with adsorption at 0 mL min−1 (static adsorption), the initial adsorption rate and the maximum adsorption capacity increased 18.8-fold and 73.8-fold at 300 mL min−1, respectively. The optimal equilibrium absorption capacity (per projected area of TiO2 NTA) and the initial adsorption rate were 2042.92 mg m−2 and 108.51 mg m−2 min−1, respectively. In the subsequently electrochemical oxidation process, 99.8% of the adsorbed TCS was degraded in-situ and TiO2 NTA was regenerated simultaneously. TiO2 NTA electrode maintained the stable removal performance of TCS during four adsorption-degradation cycles. The adsorption process was a complex combination of the hydrophobic interaction and electrostatic interaction with/without applied voltage at different pH value. The electrochemical degradation pathways of TCS on TiO2 NTA were hydroxylation, disproportionation, dichlorination and cleavage of ether bond under the attack of electrochemical generated OH and O2 −. The flow-through sequential adsorption and electrochemical degradation (SAED) based on TiO2 NTA REM were proved to be effective method to removal TCS in waters, especially for the water with low conductivity.

The current study presents a comprehensive and novel attempt to degrade aqueous tri(2-chloroethyl) phosphate (TCEP) by metal-oxide-coated Ti anodes for the first time. Six metal-oxide-coated Ti electrodes (Ti/SnO2-Sb, Ti/SnO2-Sb/PbO2, Ti/SnO2-Sb/La-PbO2, Ti/SnO2-Sb/Ce-PbO2, Ti/SnO2-Sb/Ga-PbO2 and Ti/SnO2-Sb/Zr-PbO2) were prepared and characterized. Ti/SnO2-Sb/La-PbO2 showed the highest pseudo-first-order reaction rate constant (2.1 × 10−2 min−1) and lowest energy consumption (21.35 Wh L−1) in the degradation of 1 mg L−1 TCEP at 10 mA cm−2, mainly because of its highest oxygen evolution potential and OH production. Higher current density and neutral condition favored TCEP degradation, while the presence of Cl− or NO3− could suppress the degradation. In the electrochemical degradation of 10 mg L−1 TCEP, mineralization percentage of 48.0% (mineralization current efficiency of 0.30%) and PO43− release percentage of 72.7% were achieved at 150 min. By the attack of OH on the C O and C Cl bonds in TCEP molecular structure, products of chloroethanol, Cl− and PO43− were released, with the major electrocatalytic degradation pathways of dechlorination and hydroxylation. Based on the results of flow cytometry, the relative toxicity to Escherichia coli effectively decreased to 4.93% in TCEP degradation. Compared with the UV-AOPs, electrochemical oxidation process is proved to be feasible and effective for mineralization and detoxification of TCEP in water.

The utilization of photocatalytic technology to remove air pollutants has attracted global interest. However, it still suffers from low removal activities under visible light irradiation. In this study, we demonstrated that the switching of the semiconducting behavior from n-type to p-type can efficiently improve the photocatalytic activity of g-C3N4 for nitric oxide (NO) removal about 3.5 times. This is due to that such switching could change the majority of carriers in g-C3N4 from electrons to holes. Interestingly, the photocatalytic removal of NO in both n-type and p-type g-C3N4 is proceeded via hole oxidation. More importantly, p-type g-C3N4 displays strong stability in both photocatalytic performance and crystal structures. This study provides a new strategy to improve the photocatalytic activity of semiconductors for air pollution removal.

2, 4-dichlorophenol (2, 4-DCP) is considered to be a highly toxic, mutagenic, and possibly carcinogenic pollutant. This study is focused on the electrochemical oxidation of 2, 4-DCP on nanostructured 3D-porous Ti/Sb-SnO2-Gr anodes, with the aim of presenting a comprehensive elucidation of mineralization process through the investigation of influential kinetics, the reactivity of hydroxyl radical's and analysis of intermediates. High efficiency was achieved at pH of 3 using Na2SO4 electrolytes at a current density of 30 mA cm-2. Under the optimized conditions, a maximum removal of 2, 4-DCP of up to 99.9% was reached, whereas a TOC removal of 81% was recorded with the lowest ECTOC (0.49 kW h g-1) within 40 min of electrolysis. To explore the stability of the 3D-Ti/Sb-SnO2-Gr electrodes, a continuous electrochemical operation was established, and the consistent mineralization results indicated the effectiveness of the 3D-Ti/Sb-SnO2-Gr system concerning its durability and practical utilization. EPR studies demonstrated the abundant generation of OH radicals on 3D-Ti/Sb-SnO2-Gr, resulting in fast recalcitrant pollutant incineration. From dechlorination and the reactivity of the OH radicals, several intermediates including six cyclic byproducts and three aliphatic carboxylic acids were detected, and two possible degradation pathways were proposed that justify the complete mineralization of 2, 4-DCP.

Heterojunction is recognized as an effective approach to improve photocatalytic performance, but a well-matched energy band alignment is critical therein. In this work, the shuriken-shaped BiVO 4 /TiO 2−x heterojunction is built by engineering the electronic structure of TiO 2 with Ti 3+ self-doping via a two-step hydrothermal process to achieve a high photocatalytic performance. The presence of Ti 3+ creates a defect energy level under the conduction band of TiO 2 , and thereby diminishes the interfacial energy barrier between BiVO 4 and TiO 2 . The Ti 3+ defect energy level promotes the electron transfer from BiVO 4 to conduction band of TiO 2−x . The test of phenol degradation under 300 W Xenon lamp equipped with UV cut-off filter (λ ≥ 420 nm) demonstrates that BiVO 4 /TiO 2−x heterojunction exhibits higher photocatalytic activity than its counter parts, pure BiVO 4 and the physic mixture of BiVO 4 and TiO 2−x . The improved photocatalytic performance is mainly attributed to the heterojunction formed between BiVO 4 and TiO 2−x , which improves the separation of photogenerated charge carriers as support by comparative photocurrent and time-resolved PL spectral measurements. In addition, Ti 3+ self-doping also narrows the bandgap of TiO 2 and enhances the visible-light activity of TiO 2 . The holes of TiO 2−x transfer to the valance band of BiVO 4 which further significantly improves the separation of photogenerated charge carriers, further. Additionally, the high surface area caused by TiO 2-x also contributes to the improved photocatalytic efficiency.

Nanostructured highly porous 3D-Ti/Sb–SnO2–Gr electrode, based on 3D porous graphene hydrogel was fabricated via a fast-evaporation technique through layer by layer (LBL) deposition. The 3D pores are uniformly distributed on the high fidelity of substrate with pore sizes of 7–12 nm, as confirmed by SEM analysis. Compared to Ti/Sb–SnO2 electrode, the fabricated 3D porous electrode possesses high oxygen evolution potential (2.40 V), smaller charge transfer resistance (29.40 Ω cm−2), higher porosity (0.90), enhanced roughness factor (181), and larger voltammetric charge value (57.4 mC cm−2). Electrocatalytic oxidation of Rhodamine B (RhB) was employed to evaluate the efficiency of the fabricated 3D-Ti/Sb–SnO2–Gr anode. The results show that the electrochemical reaction follows pseudo first order kinetics with rate constant (k) value of 4.93 × 10−2 min−1, which is about 3.91 times higher compared to flat Ti/Sb–SnO2. The fabricated electrode demonstrates better stability and low specific energy consumption signifying its potential usage in electrocatalysis.

The SrBi 2 Nb 2 O 9 platelets with a thickness of about 600 nm were synthesized by molten salt synthesis method. The treatment of the SrBi 2 Nb 2 O 9 platelets with hydrochloric acid resulted in the formation of the protonated H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets. Through a top–down approach in ethylamine solution, the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets were exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets with a thickness of about 2.6 nm. The evolution of the structure, composition, morphology, optical, and photocatalytic properties of SrBi 2 Nb 2 O 9 platelets was studied as it is converted into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets and subsequently exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets. The absorption edge shifts to a lower wavelength accompanied by the protonation and exfoliation. The photocatalytic H 2 evolution of the three samples were evaluated under the irradiation of a 300 W Xenon lamp from CH 3 OH/H 2 O solution, indicating that H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets Exhibit 5.5 and 26.2 times higher activity than that of the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 and SrBi 2 Nb 2 O 9 platelets, respectively. The enhanced activity for the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets is mainly attributed to the higher separation efficiency of the photogenerated carriers and the larger specific surface area caused by the significant reduction in thickness.

Polymer vesicles, also known as polymersomes, are finding increasing applications in biomedical field, including drug delivery, gene therapy, magnetic resonance imaging, theranostics, etc. This is due to their intrinsic hollow nanostructure and compartmentalized domains with diverse functionalities. This review describes recent advances in the design and synthesis of polymer vesicles, including the formation mechanisms, preparation methods, applications and responsive behaviors toward external stimuli. We first present the rational design and synthesis of polymer vesicles based on different polymeric building blocks, followed by an insight into the structure and formation mechanism of polymer vesicles, as well as the recently developed means to determine the exact thickness of the vesicle membrane. Except for responding to traditional stimuli such as pH, temperature and oxidation/reduction, polymer vesicles are becoming ‘smarter’ owing to the newly developed stimuli including electrical field, magnetic field, sugar molecules, gas, ultrasound, etc. Finally, the potential applications of polymer vesicles beyond biomedical field are highlighted as novel nanoreactors, water remediation materials, etc.

Phenol degradation with TiO2 has attracted a great deal of interest in recent years. However, its low efficiency under solar radiation and difficulty of recovery limit the potential use. Here we report a novel “silica support inducing oxygen vacancies” strategy to prepare visible-light-active TiO2 with mixed-phase, which show excellent photocatalytic performance for phenol degradation under visible light. Hydroxyl and superoxide radicals were the main oxidative species responsible for the degradation of phenol. Our work demonstrates that coupling with oxygen vacancy creation and silica nanosheets (SNSs) immobilization for TiO2 is a new approach to obtained efficient visible-light photocatalysts for practical application.

One major side effect of chemotherapy young cancer women suffer is ovarian damage. Therefore, it is necessary to study the pathogenesis of chemotherapeutic drugs for developing pharmaceutical agents to preserve fertility. Epirubicin is one of the commonly used chemotherapy drugs for breast cancer patients. This research explored the side effects of epirubicin in mice. We found that epirubicin significantly reduced the body weight, the weight of the ovaries and uteri, and the pups' number, while melatonin is extremely resistant to oxidation, significantly reduced these damages. Moreover, treatment together with melatonin prevented epirubicin caused decrease of E2 and progesterone and the loss of follicles. Mechanism study discovered that melatonin significantly reduced the levels of proapoptotic genes p53, Caspase3, and Caspase9 while upregulated antiapoptotic factors Bcl-2, Bcl2l1, and antioxidant genes superoxide dismutase 1 and catalase compared with epirubicin group. In addition, melatonin markedly reduced reactive oxygen species (ROS) and the transcription of Caspase12 and Chop, which is vital in endoplasmic reticulum stress (ERS) mediated apoptosis. These results indicate melatonin protects against epirubicin caused ovarian damage through reducing ROS caused ERS. Therefore, melatonin has therapeutic potential for the protection of ovarian function and preservation of fertility during chemotherapy. Funding Statement: This study was supported by grants from National Key R&D Program of China (2017YFC1001403), and NSFC (31871512 and 31671199) to C. Z. Support was also obtained by grant from the Major Program of the National Natural Science Foundation of China (NSFC) (81490743) to Z.-J.C., and by the Shanghai Commission of Science and Technology (17DZ2271100). Declaration of Interests: The authors declare that there are no conflicts of interest. Ethics Approval Statement: Mice were treated according to the Guidelines of Shandong Normal University for the Care and Use of Laboratory Animals.

This work presented a three-dimensional (3D) hierarchically microporous biochar (HMB) via molten alkali treatment that achieved efficient adsorption of perfluorinated carboxylic acids (PFCAs), which was a significant environment concern due to the global distribution and potential health risks. The systematic optimization of fabrication process rendered the HMB large surface area and uniform microporous structure, leading to a high adsorption capacity and adsorption rate of 1269 mg/g and 197 mg/(g·min), respectively, when perfluorooctanoic acid (PFOA) was as a representative. The adsorption mechanisms were explored via controlling the interaction between PFCAs and the HMB900-2.4. Specifically, hydrophobic effect was verified by the enhanced adsorption performance with the increase of the PFCAs homologues hydrophobicity. The observed highly pH-dependent adsorption capacity additionally suggested the dominant contribution of electrostatic interaction. For long-chain PFCAs (CnF2n+1COOH, n > 5), the HMB900-2.4 presented a high removal efficiency (> 90%) within 30 min. Even for short-chain PFCAs (CnF2n+1COOH, n = 4–5), the removal efficiency reached to over 60%. The synthesized HMB900-2.4 exhibited high stability during recycling experiments and superior performance over commercial adsorbents, suggested a promise of utilizing it to remove PFCAs from wastewater.

The effective electrochemical oxidation of aqueous carbamazepine (CBZ) using a novel blue-colored TiO2 nanotube arrays (BC-TiO2NTA) membrane filter anode was studied. The BC-TiO2NTA was characterized using SEM, TEM, BET, mercury intrusion porosimetry, XPS, XRD, CV, and LSV. The BC-TiO2NTA had reserved pore structure, formed mesopores, specific and electroactive surface areas of 2.01 m2 g-1 and 9.32 cm2 cm-2, respectively. The oxygen evolution potential was 2.61 V vs. SCE. CBZ could be degraded by OH, SO4- and O2- on BC-TiO2NTA in accordance to pseudo-first-order kinetic, which was greatly enhanced in flow-through mode. The optimal kinetic rate constant of CBZ degradation of 0.403 min-1 was achieved at 3 mA cm-2, while energy consumption per order was 0.086 kW h m-3. The mineralization efficiency and mineralization current efficiency were 50.8 % and 9.5 % at 180 min, respectively. The presence of Cl- (0.3-3 mM) accelerated electrochemical degradation of CBZ, while NO3- (0.1-2 mM) inhibited the reaction. Based on density functional theory calculation and UPLC-Orbitrap-MS/MS measurement, we found that electrochemical degradation of CBZ was initialized by cleavage of -CONH2 group and attack of OH on the olefinic double bond of the central heterocyclic ring.

In this research, Methylene blue (MB), a type of environmental pollutants (dye), was initially adopted as a carbonaceous precursor to synthesize activated carbons (ACs) with the activation of ZnCl2 at high temperatures. Varieties of techniques have been used to characterize the MB-derived ACs. The pore structures and surface functional groups were fully studied by N2 adsorption-desorption analysis, XPS, IR, SEM and TEM, respectively. The MB-derived ACs have as large specific surface area as up to 2151.92 m2g−1 and the pore size distribution concentrates on 2–5 nm. Moreover, electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge (GCD) were employed to assess AC’s capacitive behavior and rate performance. It demonstrated that MB-derived ACs possessed as high specific capacitance as 265 Fg−1 at a scan rate of 5 mV s−1 in 1 M H2SO4. In addition, the MB-derived ACs exhibited long-term cycling stability and more than 90% original capacity have been maintained after first 1000 cycles (the total cycles of 10000 were carried out.) at a high current density of 1 A g−1.

Charge separation is crucial for increasing the activity of semiconductor-based photocatalysts. In this work, a series of non-centric structure materials: K 3 ZnB 5 O 10 (KZBO), K 2 NaZnB 5 O 10 (KNZBO) and Na 3 ZnB 5 O 10 (NZBO), called nonlinear optical materials, show high activity in the chlorophenols dechlorination under UV–vis light irradiation ( λ > 254 nm). The obtained dechlorination efficiency is one order of magnitude higher than that of commercial P25 TiO 2 catalyst under same reaction conditions. Such materials possess a spontaneous polarization arising from the displacement of the center of the positive and negative charges, providing a driving force for the separation of photogenerated electrons and holes and thereby mitigating the effect of charge recombination as confirmed by Kelvin probe force microscopy. The present work implies that the nonlinear optical materials hold promise in degradation of organic chlorinated pollutants.

Nanosized metallic copper could be a replacement of noble metals for improving photoactivity of TiO2-based photocatalysts, but it tends to be oxidized by oxygen in surroundings. To avoid this, black TiO2−coated Cu nanoparticles (denoted as Cu@TiO2) were constructed in the present work, and their photoactivity for the photoreaction of CO2 with H2O vapor under visible-light irradiation was explored. X-ray diffraction, transmission electron microscopy and selected area electron diffraction analysis for the used Cu@TiO2 confirm the hierarchical structure of Cu@TiO2 and oxygen resistance of metallic Cu. The photocatalytic activity for Cu@TiO2 (∼4%Cu) reaches 1.7 times of that for its counterpart, bared black TiO2. The improved photoactivity is attributed to the embedded metallic Cu, which promotes the formation of oxygen vacancies in TiO2 through the metal-oxide interaction, thus increasing the visible-light absorption of Cu@TiO2 and the adsorption of CO2 on their surface. Furthermore, the metallic Cu increases photoinduced charge-separation of TiO2 through trapping electrons as evidenced by transient photocurrent measurements. The present work sheds light on developing new type of metal-oxide based visible-light-driven photocatalysts.

钽酸盐光催化材料往往具有较高的光催化活性.近年报道的钽酸盐光催化剂主要采用传统高温固相法制备,该方法不可避免地导致高温烧结,使合成的钽酸盐颗粒较大,比表面积较小,而且该方法具有不可克服的晶体转变、结晶度差、分解、挥发和纯度低等缺点,使制备的光催化剂活性较低.而纳米材料由于粒径小,提高了电子和空穴的扩散速度,大大降低了电子和空穴在材料内的复合几率,从而使光催化材料活性大幅提高.此外,粒径减小也使表面原子迅速增多,减小了光的漫反射,同时也使光吸收不易达到饱和,有利于提高光吸收效率.因此,制备纳米材料是提高半导体光催化剂活性的有效手段.目前,采用湿化学的溶液合成方法能在较低温度下获得粒度小且均匀、计量比准确的光催化剂粉末,但是合成钽酸盐光催化剂的水溶性钽前体即乙醇钽(或氯化钽)价格昂贵,而且对潮湿极端敏感易水解,使产物纯度降低,不适合工业化生产.近年来,尽管有文献报道以Ta2O5为原料利用水热、溶胶-凝胶和共沉淀等方法制备钽酸盐,但其合成条件苛刻,合成步骤复杂,合成周期较长,耗能大,产物产量较低且不均匀,很难实现产物的形貌控制来筛选出适合光催化反应的材料.目前关于纳米钽酸盐光催化材料形貌控制方面的研究鲜有报道,主要是由于Ta2O5极难溶解,很难实现液相合成.因此,纳米钽酸盐光催化材料的可控制备是研究的难点.我们发展了熔盐-水热制备钽酸盐新方法,实现了K1.9Na0.1Ta2O6m2H2O的可控制备.利用熔盐法制备一种可溶性钽酸盐前驱体,再通过水热法在液相进一步反应制得纳米钽酸盐光催化材料K1.9Na0.1Ta2O6m2H2O,通过控制反应条件实现了纳米钽酸盐K1.9Na0.1Ta2O6m2H2O的形貌调控,得到了纳米球、微球、去顶八面体形貌和类似榴莲形貌等不同形貌,而利用其它制备方法很难控制钽酸盐的形貌.另外,研究了制备材料吸附和光催化降解罗丹明B的性能,发现该材料光催化活性与形貌直接相关.表征结果表明,制备样品的X射线衍射(XRD)谱图尖锐,结晶较好,其各衍射峰位置均与K2Ta2O6一致,为纯相烧绿石结构,属于立方晶系,空间群为Fd3m.通过分析合成材料的元素组成及含量,确定K:Na:Ta比例近似为1.9:0.1:2.为了进一步研究属于烧绿石型化合物K1.9Na0.1Ta2O6m2H2O的结构,对不同形貌材料进行了红外光谱测试,所有样品在450n1000 cmn1的谱峰可归属于(K,Na)nO和TanO键的振动,3300 cmn1左右为晶体结构中水的羟基伸缩振动峰,1720 cmn1左右是晶体结构中水的弯曲振动峰.可以看出,不同形貌材料的红外谱图吸收带宽度和位置十分相似,只存在小的偏移和变化,进一步表明不同形貌的材料具有相似的晶体结构,与XRD结果一致.差热-热重分析确定了结构中所含结晶水数量近似为2.光催化性能测试结果表明,具有纳米球形貌的材料比表面积较大,因而光催化活性最高.

NiCrAlY coating was plasma-sprayed on a Ni-based single crystal superalloy and then subjected to isothermal oxidation at 1100 C in air up to 50 h. Using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), we investigate interfacial microstructure evolution of the coating induced by internal oxidation and nitridation. After 5 h oxidation, a-Al2O3 and Cr2O3 sub-layers form at the coating/substrate interface. Interestingly, after 10 h oxidation, pure Al phase is found at the coating/substrate interface owing to decomposition of substrate phase c 0 -Ni3Al. Although, after 25 h oxidation, hexagonal AlN and cubic TiN form in the substrate close to the coating/substrate interface, after 50 h oxidation, AlN transforms into a-Al2O3 owing to internal oxidation while TiN remains in the substrate because of its high stability. The findings of this work provide solid experimental evidence of microstructural evolution at the coating/substrate interface, especially demonstrate the conjecture that pure metal phases and nitrides could precipitate at coating/substrate interface after high temperature oxidation.

In recent years, methicillin-resistant Staphylococcus aureus (MRSA) has become one of the most common multi-drug resistant bacteria in both hospital and community. The aim of this study is to investigate the selective inhibition of MRSA by a modified photosensitizer (LAEtNBS) in vitro and the efficacy of MRSA infection treatment by photodynamic therapy (PDT) with LAEtNBS in vivo. LAEtNBS was synthesized by adding a cationic photosensitizer molecule (EtNBS-COOH) and a quencher molecule to two side chains of cephalosporin, which was then shown to have similar absorption and emission wavelengths with EtNBS-COOH, but suppressed yields of fluorescence quantum and singlet oxygen. The selective inactivation and less phototoxicity of LAEtNBS, compared to that of EtNBS-COOH, were assessed and confirmed by conducting PDT to two Staphylococcus aureus strains and human skin cells at a fluence of 15 J/cm(2) with 640±10 nm LED light. Furthermore, using mouse skin wound model infected with 10(8) CFU of MRSA, we found that both LAEtNBS and EtNBS-COOH were able to treat MRSA infection and enhance wound repair. However, there was no significant difference in the two photosensitizers that might be due to the environment in vivo. Modification of the photosensitizer will be very beneficial for developing new strategies to treat drug resistant bacterial infection with less harm to host tissue.

In this work, we proposed a facile method for preparation of hierarchical porous ceramic membrane with energetic catalytic ozonation capability aiming at enhancing the performance of water treatment by using the combined ozone-membrane system. The strategy involved preparation of TiO2 macroporous membrane as a backbone and subsequently coating it with mesoporous Ti–Mn catalyst layer. Scanning electron microscope, transmission electron microscope and nitrogen sorption isotherms characterization demonstrated that the TiO2 membrane was composed of TiO2 nanorods with 200–400 nm diameter, 5 μm length, and mesoporous Ti–Mn layer was coated on the membrane surface uniformly with the thickness of about 100 nm and pore size of 10 nm. Energy dispersive X-ray spectroscopy, X-rays photoelectron spectroscopy and X-ray diffractometer showed that Ti–Mn mixed oxide was spread into the inner voids of the membrane to form a hierarchical porous structure. Treating simulated wastewater (aqueous solution of dye Red-3BS and Aniline) it was found that hierarchical porous catalytic membrane exhibited high catalytic ozonation capability which resulted in an enhancement of membrane antifouling, separation and degradation of organic pollutants when the membrane was used as a key device in the combined membrane and ozone system.

Sn-doped octahedronal and tetrakaidecahedronal In2O3 particles were successfully synthesized by simple thermal evaporation of indium grains using SnO as dopant. Structural characterization results demonstrated that the Sn-doped tetrakaidecahedronal In2O3 particle had additional six {001} crystal surfaces compared with the octahedronal one. The luminous properties of both samples were characterized by photoluminescence (PL) and cathodoluminescence (CL) spectroscopy. A broad visible luminous emission around 570 nm was observed. Studies revealed that the emission consisted of three peaks of 511 nm, 564 nm, and 622 nm, which were attributed to radioactive recombination centers such as single ionized oxygen vacancy, indium interstitial, and antisite oxygen, respectively. We believe that the Sn donor level plays an important role in the visible luminous emission.

The novel two-dimensional (2-D) Ga-doped In 2 O 3 nanoleaves are synthesized by a simple one-step carbonthermal evaporation method using Cu–Sn alloy as the substrates. Two basic parts construct this leaf-like nanostructure: a long central trunk and two tapered nanoribbons in symmetric distribution in relation to the trunk. The Ga–In–O alloy particles are located at or close to the tips of the central trunks and serve as catalysts for the central trunk growth by the self-catalytic vapor–liquid–solid (VLS) mechanism. And the homoepitaxial growth of tapered nanoribbon on the surface of the central trunk can be explained by vapor–solid (VS) mechanism. The room-temperature photoluminescence (PL) measurement of this nanoscaled Ga-doped In 2 O 3 transparent conducting oxide (TCO) detected two blue peaks located at 432 nm and 481 nm, respectively, which can be used by Ru-based dye and indicates potential application in dye-sensitized solar cells (DSSCs). The successful preparation of this novel 2-D Ga-doped In 2 O 3 nanoleaves not only enriches the synthesis of TCO materials, but also provides new blocks in future architecture of functional nano-devices.

Hexagonal SnS2 particles were synthesized via a solvothermal method using a mixture of ethylene glycol (EG) and distilled water as solvent. Hexagonal SnS2 nanoplates of more regular morphology were obtained when the volumetric ratio of EG to distilled water (EG:H2O) decreased from 4:1 to 1:4. The effect of EG on the growth of hexagonal SnS2 nanoplates was investigated and a growth restraint mechanism in [0 0 1] was proposed. A large band gap of 3.52 eV of the hexagonal SnS2 nanoplates may facilitate electron injection from photo-excited dye molecules in dye-sensitized solar cells (DSSCs). A photoluminescence (PL) peak at 761 nm under excitation at 507 nm was also observed in the hexagonal SnS2 nanoplates. The 761 nm emission, which is within the absorption band of the Ru-based dye, is expected to make sufficient utilization of solar energy in DSSCs.

Urchin-like ZnO nanostructures have been synthesized by a two-step thermal evaporation method. The product was characterized with scanning electron microscopy, X-ray powder diffraction, transmission electron microscopy, and spectrofluorometry. The results of characterization revealed that the urchin-like ZnO nanostructure consists of a spherical metallic Zn core and wurtzite ZnO nanowires growing on the surface of the ZnO buffer which covers the Zn core and the growth directions of wurtzite ZnO nanowires are along . According to the analysis on these results, a possible two-step growth mechanism was proposed to explain the formation of the urchin-like ZnO nanostructures. The fluorescence-emission mechanisms were also discussed.