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[Display omitted] Type 1 diabetes mellitus is an auto-immune disease causing the T -cell mediated destruction of insulin-producing β-cells, resulting in chronic hyperglycemia. Current treatments such as insulin replacement therapy or the transplantation of pancreas or pancreatic islets present major disadvantages such as the constant need of drugs, as well as a shortage of donor organs. In this review, we discuss a sustainable solution to overcome these limitations combining the use of β-cells, derived from stem cells, and their encapsulation within a protective matrix. This article provides an exhaustive overview of currently investigated stem cell sources including embryonic, mesenchymal as well as induced pluripotent stem cells in combination with various up to date encapsulation methods allowing the formation of immuno-protective devices. In order to identify current limitations of this interdisciplinary therapeutic approach and to find sustainable solutions, it is essential to consider key aspects from all involved domains. This includes biological parameters such as the stem cell origin but also the different aspects of the encapsulation process, the used materials and their physico-chemical properties such as elasticity, porosity and permeability cut-off as well as the best implantation sites allowing efficient and self-autonomous control of glycemia by the transplanted encapsulated cells. [ABSTRACT FROM AUTHOR]

Abstract: Unusual partially crystalline ordered mesoporous zirconosilicate doughnuts with Si/Zr ratio as low as 1.5 were synthesized from the aqueous polymerisation of a single source molecular precursor Zr[OSi(Ot-BuO)3]4 without the use of any templating agent. A radial homogenous mesoporosity (4nm) was observed inside these very regular sub-micrometric (600nm) doughnuts. These structures were partially crystallized in hydrothermal conditions (100°C) into an analogous zircon (ZrSiO4) framework. The formation mechanism has been investigated. It is evidenced that chlorine anions Cl− concentration and pH value are essential to achieve the process, even if their role is still a matter of investigations. The obtained materials demonstrated even higher catalytic activity, selectivity and stability in the liquid oxidative dehydrogenation of hydroquinone to 1,4-benzoquinone compared to TS-1 zeolite catalysts and amorphous highly ordered mesoporous zirconosilicate materials. [Copyright &y& Elsevier]

Abstract: A layer of macrocyclic calix[4]arene derivatives has been grafted on the internal surface of the mesochannels of the ordered mesoporous SBA-15 to develop highly efficient trap for heavy transition metal (HTM) ions. To ensure the successful anchoring of calix[4]arene derivatives on the surface of SBA-15, two different types of calix[4]arene derivatives, one with one trimethoxysilane functional group and another with two trimethoxysilane functional groups have been explored. XRD, N2 adsorption and TEM results provide strong evidence that the mesoporous structure of the supporting materials retain their long range ordering throughout the grafting process. Solid-state NMR, TG and FT-IR spectroscopy indicate that both types of calix[4]arene derivatives can be well-anchored on the surface of the wall of SBA-15. Calix[4]arene derivative with only one trimethoxysilane functional group showed high grafting efficiency compared to that with two trimethoxysilane functional groups due to the intramolecular and intermolecular polycondensation between two trimethoxysilane functional groups. The HTM ions extraction capacity in aqueous solution of macrocycle functionalized SBA-15 nanohybrides for a series of HTM ions has been studied. The obtained materials demonstrated very high HTM ions extraction capacity up to 96% for Pb2+ in aqueous solution. [Copyright &y& Elsevier]

Abstract: Highly sensitive and selective nanosensor for labile iron pool (LIP) determination, has been designed and prepared by immobilization of Fluoresceine–Desferrioxamine (Fl–DFO), a bifunctional fluoro-siderophore probe molecule with great affinity for iron ions (pKf =30.7), into highly ordered mesoporous silica structure. Different immobilization methods of Fl–DFO molecules, such as their encapsulation in surfactant micelles used as templating agents for the synthesis of mesoporous silica, direct impregnation into the mesochannels of as-synthesized mesoporous silica and their surface anchoring by covalent binding with propylamine groups implanted by post-synthesis on the internal surface of mesochannels, have been explored. Each nanohybrid has been fully characterized by small angle XRD, TEM, SEM, solid state 29Si and 13C MAS NMR and N2 adsorption–desorption. The fluorescence properties of nanohybrids obtained have been correlated with the immobilization methods, generating interesting information concerning the localization of Fl–DFO molecules in the channels of mesoporous silica. The leaching of Fl–DFO molecules from mesoporous materials has been investigated. The nanosensor prepared by surface anchoring of Fl–DFO at the internal surface of mesochannels showed high performances with no leaching effect and high sensitivity in regards to its responses to ferric ions. Its fluorescence intensity decreased as soon as first FeIII ions are in contact with this nanosensor. A linear relationship between the fluorescence intensity and the ferric ions concentration was observed in low micromolar range. The selectivity of this nanosensor towards other metal ions has also been tested and shown its high affinity to ferric ions. This study can allow the design of a stable, portable, simple, regenerable and cost-effective nanosensor highly sensitive and selective for iron ions with detection limits in the range of cellular LIP in cells, e.g. lower micromolar range. [Copyright &y& Elsevier]

[Display omitted] Solar-light driven oxidation of benzylic alcohols over photocatalysts endows significant prospects in value-added organics evolution owing to its facile, inexpensive and sustainable process. However, the unsatisfactory performance of actual photocatalysts due to the inefficient charge separation, low photoredox potential and sluggish surface reaction impedes the practical application of this process. Herein, we developed an innovative Z-Scheme Cs 3 BiBr 9 nanoparticles@porous C 3 N 4 tubes (CBB-NP@P-tube-CN) heterojunction photocatalyst for highly selective benzyl alcohol oxidation. Such composite combining increased photo-oxidation potential, Z-Scheme charge migration route as well as the structural advantages of porous tubular C 3 N 4 ensures the accelerated mass and ions diffusion kinetics, the fast photoinduced carriers dissociation and sufficient photoredox potentials. The CBB-NP@P-tube-CN photocatalyst demonstrates an exceptional performance for selective photo-oxidation of benzylic alcohol into benzaldehyde with 19, 14 and 3 times higher benzylic alcohols conversion rate than those of C 3 N 4 nanotubes, Cs 3 Bi 2 Br 9 and Cs 3 Bi 2 Br 9 @bulk C 3 N 4 photocatalysts, respectively. This work offers a sustainable photocatalytic system based on lead-free halide perovskite toward large scale solar-light driven value-added chemicals production. [ABSTRACT FROM AUTHOR]

[Display omitted] The voltage decay of Li-rich layered oxide cathode materials results in the deterioration of cycling performance and continuous energy loss, which seriously hinders their application in the high-energy–density lithium-ion battery (LIB) market. However, the origin of the voltage decay mechanism remains controversial due to the complex influences of transition metal (TM) migration, oxygen release, indistinguishable surface/bulk reactions and the easy intra/inter-crystalline cracking during cycling. We investigated the direct cause of voltage decay in micrometer-scale single-crystal Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 (SC-LNCM) cathode materials by regulating the cut-off voltage. The redox of TM and O2− ions can be precisely controlled by setting different voltage windows, while the cracking can be restrained, and surface/bulk structural evaluation can be monitored because of the large single crystal size. The results show that the voltage decay of SC-LNCM is related to the combined effect of cation rearrangement and oxygen release. Maintaining the discharge cutoff voltage at 3 V or the charging cutoff voltage at 4.5 V effectively mitigates the voltage decay, which provides a solution for suppressing the voltage decay of Li-rich and Mn-based layered oxide cathode materials. Our work provides significant insights into the origin of the voltage decay mechanism and an easily achievable strategy to restrain the voltage decay for Li-rich and Mn-based cathode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] The conversion of CO 2 into syngas, a mixture of CO and H 2 , via photocatalytic reduction, is a promising approach towards achieving a sustainable carbon economy. However, the evolution of highly adjustable syngas, particularly without the use of sacrifice reagents or additional cocatalysts, remains a significant challenge. In this study, a step-scheme (S-scheme) 0D ZnGa 2 O 4 nanodots (∼7 nm) rooted g-C 3 N 4 nanosheets (denoted as ZnGa 2 O 4 /C 3 N 4) heterojunction photocatalyst was synthesized vis a facial in-situ growth strategy for efficient CO 2 -to-syngas conversion. Both experimental and theoretical studies have demonstrated that the polymeric nature of g-C 3 N 4 and highly distributed ZnGa 2 O 4 nanodots synergistically contribute to a strong interaction between metal oxide and C 3 N 4 support. Furthermore, the desirable S-scheme heterojunction in ZnGa 2 O 4 /C 3 N 4 efficiently promotes charge separation, enabling strong photoredox ability. As a result, the S-scheme ZnGa 2 O 4 /C 3 N 4 exhibited remarkable activity and selectivity in photochemical conversion of CO 2 into syngas, with a syngas production rate of up to 103.3 μ mol g−1 h−1, even in the absence of sacrificial agents and cocatalyst. Impressively, the CO/H 2 ratio of syngas can be tunable within a wide range from 1:4 to 2:1. This work exemplifies the effectiveness of a meticulously designed S-scheme heterojunction photocatalyst for CO 2 -to-syngas conversion with adjustable composition, thus paving the way for new possibilities in sustainable energy conversion and utilization. [ABSTRACT FROM AUTHOR]

[Display omitted] Manipulation of light has been proved to be a promising strategy to increase light harvesting in solar-to-chemical energy conversion, especially in photocatalysis. Inverse opal (IO) photonic structures are highly promising for light manipulation as their periodic dielectric structures enable them to slow down light and localize it within the structure, thereby improving light harvesting and photocatalytic efficiency. However, slow photons are confined to narrow wavelength ranges and hence limit the amount of energy that can be captured through light manipulation. To address this challenge, we synthesized bilayer IO TiO 2 @BiVO 4 structures that manifested two distinct stop band gap (SBG) peaks, arising from different pore sizes in each layer, with slow photons available at either edge of each SBG. In addition, we achieved precise control over the frequencies of these multi-spectral slow photons through pore size and incidence angle variations, that enabled us to tune their wavelengths to the electronic absorption of the photocatalyst for optimal light utilization in aqueous phase visible light photocatalysis. This first proof of concept involving multi-spectral slow photon utilization enabled us to achieve up to 8.5 times and 2.2 times higher photocatalytic efficiencies than the corresponding non-structured and monolayer IO photocatalysts respectively. Through this work, we have successfully and significantly improved light harvesting efficiency in slow photon-assisted photocatalysis, the principles of which can be extended to other light harvesting applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CNTs interconnected yolk-shell Si/C anode (YS-Si@CoNC) is designed via the chelation competition-induced polymerization (CCIP) for LIBs. • The CNTs and carbon shell provide an excellent electronically conductive network for the fast diffusion of electrons and Li+. • The unique yolk-shell structure greatly reduces the volume expansion of SiNPs in the cycling. • The YS-Si@CoNC anode presents outstanding electrochemical performances and structural stability. As a viable replacement to commercial graphite anodes, silicon (Si) anodes have gained much attention from academics because of their considerable theoretical specific capacity and appropriate reaction voltage. Nevertheless, some limitations still exist in developing silicon anodes, including significant volume expansion and poor electrical conductivity. Herein, the carbon nanotubes (CNTs) interconnected yolk-shell silicon/carbon anodes (YS-Si@CoNC) were prepared via the chelation competition induced polymerization (CCIP) approach. The YS-Si@CoNC anode, designed in this study, demonstrates improved performance. At the current density of 0.5 A g−1 and 1 A g−1, a capacity of 1001 mAh g−1 and 956.5 mAh g−1 can be achieved after 150 cycles and after 300 cycles, respectively. In particular, at the current density of 5 A g−1, the reversible specific capacity of 688 mAh g−1 is realized. The exceptional outcomes are mainly attributed to the internal voids that adequately alleviate the volumetric expansion and the CNTs and carbon shells that provide an efficient conducting matrix to fasten the diffusion of electrons and lithium-ions. Our research presents a convenient way of designing Si/C anode materials with a yolk-shell structure to guarantee impressive electrical conductivity and robust structural integrity for high-performance LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glucose conversion assisted photocatalytic water splitting technology avoid the use of sacrificial agents while realizing co-product of H 2 and high value-added chemicals. • Both hierarchical 3DOM structure and type Ⅱ heterojunction are conducive to the absorption and utilization of light and the separation and transmission of carriers. • The 3DOM CTO-ZCS photocatalyst simultaneously has high photocatalytic H 2 production performance (2.81 mmol g-1h−1) and high glucose conversion (85.57 %). • The conversion of glucose to lactic acid is a two-step reaction and the control reaction step is gluconic acid to lactic acid. Glucose conversion assisted photocatalytic water splitting technology to simultaneously produce H 2 and high value-added chemicals is a promising method for alleviating the energy shortage and environmental crisis. In this work, we constructing type II heterojunction by in-situ coupling Zn 0.3 Cd 0.7 S quantum dots (ZCS QDs) on three-dimensionally ordered microporous CaTiO 3 (3DOM CTO) for photocatalytic H 2 production and glucose conversion. The DFT calculations demonstrate that substitution of Zn on the Cd site improves the separation and transmission of photogenerated carriers. Therefore, 3DOM CTO-ZCS composite exhibits best H 2 production performance (2.81 mmol g-1h−1) and highest apparent quantum efficiency (AQY) (5.56 %) at 365 nm, which are about 47 and 18 times that of CTO nanoparticles (NPs). The improved catalytic performance ascribed to not only good mass diffusion and exchange, highly efficient light harvesting of 3DOM structure, but also the efficient charges separation of type Ⅱ heterojunction. The investigation on photocatalytic mechanism indicates that the glucose is mainly converted to gluconic acid and lactic acid, and the control reaction step is gluconic acid to lactic acid. The selectivity for gluconic acid on 3DOM CTO-ZCS is 85.65 %. Our work here proposes a green sustainable method to achieve highly efficient H 2 production and selective conversion of glucose to gluconic acid. [ABSTRACT FROM AUTHOR]

[Display omitted] Periodic structures with alternating refractive indices such as inverse opal photonic crystals are capable of reducing the group velocity of light such that this slowed light can be more efficiently harvested for highly enhanced solar energy conversion. However, the generation, the manipulation and, in particular, the practical applications of these slow photons remain highly challenging. Here, we report the first proof of concept on the ability to control, in an inverse opal TiO 2 -BiVO 4 hetero-composite, the transfer of slow photons generated from the inverse opal photonic structure to the photocatalytically active BiVO 4 nanoparticles for highly enhanced visible light photoconversion. Tuning the slow photon frequencies, in order to accommodate the electronic band gap of BiVO 4 for slow photon transfer and for significantly improved light harvesting, was successfully achieved by varying the structural periodicity (pore size) of inverse opal and the light incidence angle. The photocatalytic activity of BiVO 4 in all inverse opal structures, promoted by slow photon effect, reached up to 7 times higher than those in the non-structured compact films. This work opens new avenues for the practical utilization of slow photon effect under visible light in photocatalytic energy-related applications like water splitting and carbon dioxide reduction and in photovoltaics. [ABSTRACT FROM AUTHOR]

Abstract: Nature is the creation of aesthetic functional systems, in which many natural materials have vagarious structures. Inspired from nature, such as lotus leaf, butterfly’ wings, showing excellent superhydrophobicity, scientists have recently fabricated a lot of biomimetic superhydrophobic surfaces by virtue of various smart and easy routes. Whilst, many examples, such as lotus effect, clearly tell us that biomimicry is dissimilar to a simple copying or duplicating of biological structures. In this feature article, we review the recent studies in both natural superhydrophobic surfaces and biomimetic superhydrophobic surfaces, and highlight some of the recent advances in the last four years, including the various smart routes to construct rough surfaces, and a lot of chemical modifications which lead to superhydrophobicity. We also review their functions and applications to date. Finally, the promising routes from biomimetic superhydrophobic surfaces in the next are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Living cells can be considered as a highly efficient molecular engines spatially enclosed, remaining however fragile. By combining cells with silica materials in an appropriate way, novel living hybrid material technologies can be designed. After showing the real interplay between silica species and living organisms in nature, this featuring article summarizes the considerable progress in cell encapsulation into silica matrixes. Generally speaking, bioencapsulation allows protecting cells from harsh environment and controlling their surrounding as well as their concentration. This combination produces ultimately a device that can be oriented to drive the desired biochemical reactions. Particularly, this article highlights that functional living matters are very promising in the development of new eco-friendly processes. Compared to conventional chemical process, these hybrid systems would be enabled to use greater and in more efficient way renewable resources (i.e. solar energy) to produce a vast array of chemicals. Additionally, encapsulated cell technology has opened the possibility to design various other kinds of bioactive materials such as cleaning systems, biosensors and artificial organs. Through different examples, including the immobilization of microorganisms, photosynthetic organelles, plant cells and animal cells, the interests and the preparation methods of these living hybrid materials are discussed. [Copyright &y& Elsevier]

The 3DOM TiO 2 -Au-CdS inverse opal photonic crystal structure is designed for visible-light hydrogen production, exhibiting extremely enhanced photocatalytic activity via coupling bifunctional SPR effect and electron transfer of Au NPs with slow photon effect. [Display omitted] • The ternary TiO 2 -Au-CdS (TAC) photocatalysts have been designed to couple the bifunctional Au NPs with slow photon effect. • A two electron transfer paths model is proposed in the ternary TAC photocatalysts. • Finite-difference time-domain (FDTD) simulations are used to reveal the size effect of Au NPs. • The ternary TAC-10 photocatalyst with ~ 10 nm Au NPs demonstrates the highest hydrogen evolution rate under visible-light. Gold nanoparticles (Au NPs) with surface plasmonic resonance (SPR) effect and excellent internal electron transfer ability have widely been combined with semiconductors for photocatalysis. However, the in-depth effects of Au NPs in multicomponent photocatalysts have not been completely understood. Herein, ternary titanium oxide-gold-cadmium sulfide (TiO 2 -Au-CdS, TAC) photocatalysts, based on hierarchical TiO 2 inverse opal photonic crystal structure with different Au NPs sizes have been designed to reveal the SPR effect and internal electron transfer of Au NPs in the presence of slow photon effect. It appears that the SPR effect and internal electron transfer ability of Au NPs, depending on their sizes, play a synergistic effect on the photocatalytic enhancement. The ternary TAC-10 photocatalyst with ~ 10 nm Au NPs demonstrates an unprecedented hydrogen evolution rate of 47.6 mmolh-1g−1 under visible-light, demonstrating ~ 48% enhancement comparing to the sample without slow photon effect. In particular, a 9.83% apparent quantum yield under 450 nm monochromatic light is achieved for TAC-10. A model is proposed and finite-difference time-domain (FDTD) simulations reveal the size influence of Au NPs in ternary TAC photocatalysts. This work suggests that the rational design of bifunctional Au NPs coupling with slow photon effect could largely promote hydrogen production from visible-light driven water splitting. [ABSTRACT FROM AUTHOR]

The as-fabricated Mn 3 O 4 /graphene nanocomposite by a novel Mn-alkoxide nanoplates hydrolysis method exhibits excellent performance in terms of cycling performance and rate capability for lithium storage. [Display omitted] Herein we develop a novel and effective alkoxide hydrolysis approach to in-situ construct the trimanganese tetraoxide (Mn 3 O 4)/graphene nanostructured composite as high-performance anode material for lithium-ion batteries (LIBs). This is the first report on the synthesis of Mn 3 O 4 /graphene composite via a facile hydrolysis of the manganese alkoxide (Mn-alkoxide)/graphene precursor. Before hydrolysis, two dimensional (2D) Mn-alkoxide nanoplates are closely adhered to 2D graphene nanosheets via Mn-O chemical bonding. After hydrolysis, the Mn-alkoxide in-situ converts to Mn 3 O 4 , while the Mn-O bond is preserved. This leads to a robust Mn 3 O 4 /graphene hybrid architecture with 15 nm Mn 3 O 4 nanocrystals homogeneously anchoring on graphene nanosheets. This not only prevents the Mn 3 O 4 nanocrystals agglomeration but also inversely mitigates the graphene nanosheets restacking. Moreover, the flexible and conductive graphene nanosheets can accommodate the volume change. This maintains the structural and electrical integrity of the Mn 3 O 4 /graphene electrode during the cycling process. As a result, the Mn 3 O 4 /graphene composite displays superior lithium storage performance with high reversible capacity (741 mAh g−1 at 100 mA g−1), excellent rate capability (403 mAh g−1 at 1000 mA g−1) and long cycle life (527 mAg g−1 after 300 cycles at 500 mA g−1). The electrochemical performance highlights the importance of rational design nanocrystals anchoring on graphene nanosheets for high-performance LIBs application. [ABSTRACT FROM AUTHOR]

• n -p heterojunction of TiO 2 -NiO ultrafine core-shell nanoparticles are prepared. • Strong interfacial interaction significantly improve charge separation efficiency. • As-fabricated photocatalyst exhibits excellent H 2 production from water splitting. • H 2 , CH 4 and fatty acids are cogenerated from biomass lignin photoreforming. Hydrogen evolution from biomass photoreforming has been widely recognized as a promising strategy for relieving the pressure from energy crisis and environmental pollution, as it could generate sustainable H 2 and value-added bioproducts simultaneously. Combining p-type semiconductors with n -type semiconductors to form n -p heterojunction is an effective strategy to improve the photocatalytic quantum efficiency by enhancing the separation of photogenerated electrons and holes, which could greatly facilitate the realization of such biomass photorefinery concept. However, the incompact contact between the n -type and p-type semiconductors often induces the aggregation of photogenerated electrons and holes. In this work, we design and synthesize an ultrafine n -p heterojunction TiO 2 -NiO core-shell structure to overcome the incompact contact in the n -p interface. When the n -p heterojunction photocatalysts are evaluated for photocatalytic water splitting and biomass lignin photoreforming respectively, the as-fabricated TiO 2 -NiO nanocomposite with 3.25% NiO demonstrates the highest hydrogen generation of 23.5 mmol h−1 g−1 from water splitting and H 2 (0.45 mmol h−1 g−1) and CH 4 (0.03 mmol h−1 g−1) cogeneration with reasonable amount of fatty acids (palmitic acid and stearic acid) production from lignin photoreforming. The excellent photocatalytic activity is ascribed to the synergistic effects of high crystallinity of TiO 2 ultrafine nanoparticles, core-shell structure and n -p heterojunction with NiO nanoclusters. This present work demonstrates a simple and efficient method to fabricate ultrafine n -p heterojunction core-shell structure for noble-metal free catalyst for both water splitting and biomass photoreforming. [ABSTRACT FROM AUTHOR]

N, O, S co-doped hierarchically porous carbon nanobelts with fast channels and special defects exhibit high capacity and excellent cycling stability for Li-ion and Li-Se batteries. • Defect-rich HPCNBs are derived from the whole organic Melamnie-based polymer network. • N, O, S co-doping HPCNBs enhances the electrical conductivity and chemical affinity. • The Se@HPCNB nanocomposite has fast channels and dual confinement for active species. • The Se@HPCNB nanocomposite demonstrates stable and long-term cycle for Li-ion and Li-Se batteries. Li-Se battery is a promising energy storage candidate owing to its high theoretical volumetric capacity and safe operating condition. In this work, for the first time, we report using the whole organic Melamine-based porous polymer networks (MPNs) as a precursor to synthesize a N, O, S co-doped hierarchically porous carbon nanobelts (HPCNBs) for both Li-ion and Li-Se battery. The N, O, S co-doping resulting in the defect-rich HPCNBs provides fast transport channels for electrolyte, electrons and ions, but also effectively relieve volume change. When used for Li-ion battery, it exhibits an advanced lithium storage performance with a capacity of 345 mAh g−1 at 500 mA g−1 after 150 cycles and a superior rate capacity of 281 mAh g−1 even at 2000 mA g−1. Further density function theory calculations reveal that the carbon atoms adjacent to the doping sites are electron-rich and more effective to anchor active species in Li-Se battery. With the hierarchically porous channels and the strong dual physical–chemical confinement for Li 2 Se, the Se@ HPCNBs composite delivers an ultra-stable cycle performance even at 2 C after 1000 cycles. Our work here suggests that introduce of heteroatoms and defects in graphite-like anodes is an effective way to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

ZnO is known to be photocatalytic, but with limited performances due to the strong electron-hole recombination after irradiation. The integration of ZnO nanomaterials on a conductive and high surface area carbon substrate is thus a potential alternative to obtain a significant improvement of the photocatalytic performance. Moreover, the carbon functionalization is expected to have a significant role in the adsorption/degradation mechanisms of dye, due to the difference in wettability or surface charge. In this view, ZnO photocatalytic nanoparticles have been deposited on high surface area carbon xerogel substrate (C XG), using a new and original plasma process, consisting in the degradation of a solid organometallic directly on the carbon substrate (no gaseous precursor). In addition to the ZnO nanoparticle formation, the plasma treatment allows the carbon functionalization. The ZnO/C XG composite has been tested for the degradation of Rhodamine B (RhB) in aqueous media and compared with and O 2 or NH 3 plasma-treated xerogels (without nanoparticles) to identify the significant role of the substrate and its modification in the RhB adsorption and degradation mechanism. The high photocatalytic activity of ZnO/C XG composite is attributed to (i) the formation of small (8–10 nm) and well-crystallized ZnO nanoparticles anchored to the carbon substrate and (ii) to the modification of the xerogel surface chemistry. Indeed, O 2 plasma treatment of the C XG promotes the generation of hydroxyl, carbonyl and carboxyl surface functional groups, which are polar and acidic, while the NH 3 plasma treatment mainly leads to the formation of polar and basic amino groups. While both plasma treatments promote the formation of polar functional groups, which enhance the C XG wettability, the formation of acidic groups is identified as beneficial for the adsorption of the RhB dye, while basic groups are detrimental. [ABSTRACT FROM AUTHOR]

The well-designed Cu 2 O hollow nanospheres with active {1 1 0} and {1 1 1} facets can quickly remove the pollutants from water. We report the well-designed active {1 1 0} and {1 1 1} faceted Cu 2 O hollow nanospheres (Cu 2 O-HNs) for the quick removal of the high concentration pollutants in water. For the first time, these Cu 2 O-HNs combine the advantages of the active facets, hollow structure and nanostructures. The abundance of dangling Cu atoms in two active facets results in positively charged surface to effectively react with the negatively charged pollutants. The hollow structure provides the opportunity to take full use of these active sites. Consequently, the active faceted Cu 2 O-HNs demonstrate excellent adsorption and photodegradation capacities for high concentrated anionic dyes. The smallest Cu 2 O-HNs (~100 nm) can adsorb ~90% of methyl blue (MB) (100 mg L−1) in 10 min and degrade ~92% of MB (100 mg L−1) in 10 min under visible-light. In particular, a film consisting of the smallest Cu 2 O-HNs can quickly remove high concentrated organic dyes and be reused after solar light irradiation for 10 min in air, showing the promising practical application for the removal of organic pollutants. [ABSTRACT FROM AUTHOR]

MoS 2 quantum dots (QDs) in-situ directing porous MoS 2 -QDs/ZnIn 2 S 4 heterostructures exhibit the H 2 production rate under visible light. Photocatalytic hydrogen (H 2) production based on semiconductors is important to utilize solar light for clean energy and environment. Herein, we report a visible light responsive heterostructure, designed and constructed by molybdenum disulfide quantum dots (MoS 2 -QDs) in-situ seeds-directing growth and self-assemble of zinc indium sulfide (ZnIn 2 S 4) nanosheet to ensure their full contact through a simple one-step solvothermal method for highly improved visible light H 2 production. The MoS 2 -QDs in-situ seeds-directing ZnIn 2 S 4 heterostructure not only builds heterojunctions between MoS 2 and ZnIn 2 S 4 to spatially separate the photogenerated electrons and holes, but also serves as the active sites trapping photogenerated electrons to facilitate H 2 evolution. As a result, MoS 2 -QDs/ZnIn 2 S 4 exhibits high photocatalytic activity for H 2 production, and the optimized 2 wt% MoS 2 -QDs/ZnIn 2 S 4 (2MoS 2 -QDs/ZnIn 2 S 4) heterostructure exhibits the highest H 2 evolution rate of 7152 umol·h−1·g−1 under visible light, ∼9 times of pure ZnIn 2 S 4. Our strategy here could shed some lights on developing noble-metal free heterostructures for highly efficient photocatalytic H 2 production. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Novel ternary ZnO/BiVO 4 /3DOM TiO 2 nanocomposites are synthesized. • Ternary ZnO/BiVO 4 /3DOM TiO 2 nanocomposites exhibit enhanced catalytic activity. • The cascade electronic band structure in ternary nanocomposites leads to the enhanced photocatalytic performance. • Coupling semiconductors with suitable energy levels is favorable to improve the efficiency of induced light. Abstract Ternary zinc oxide/bismuth vanadate/three-dimensional ordered macroporous titanium dioxide (ZnO/BiVO 4 /3DOM TiO 2) heterojuncted nanocomposites with cascade electronic band structures were successfully designed and synthesized for visible light photodegradation of two different molecules: Rhodamine B (RhB) and Tartrazine. The photocatalytic active species have been investigated by using electron scavenger (AgNO 3) and hole scavenger (Triethanolamine: TEOA). The band edge positions of each component in tenary nanocomposites have been measured by using photoelectrochemical Mott-Schottky method and valence band XPS (VB-XPS) spectroscopy. Within the heterojunction, charges are favorably and spatially separated through the gradient potential at the interfaces. This largely suppresses the recombination of photogenerated electrons and holes. Furthermore, 3DOM inverse opal structure is beneficial for high diffusion efficiency and highly accessible surface area of reactants and light and multiple scattering for light harvesting. Consequently, these heterojuncted nanocomposites exhibit highly enhanced photocatalytic performance compared with pure BiVO 4 nanostructure, and binary BiVO 4 /3DOM TiO 2 , ZnO/BiVO 4 nanocomposites. A detailed mechanism of charge transfer is proposed for these ternary ZnO/BiVO 4 /3DOM TiO 2 nanocomposites on the basis of a large series of spectroscopic and photocatalytic results. Our work demonstrates clearly that coupling multicomponent semiconductors with different energy levels of conduction and valence bands can significantly increase the photogenerated charge carriers through the efficient charge separation across their multiple interfaces. This work gives some new ideas on developing new visible light responsive nanocomposites for highly efficient solar energy utilization. [ABSTRACT FROM AUTHOR]

Graphical abstract Hierarchically porous ZnO/g-C 3 N 4 microspheres with type-II heterojunction exhibit an enhanced photocatalytic degradation on rhodamine B and phenol. Abstract Graphitic carbon nitride (g-C 3 N 4) is a visible light active semiconductor. However, low conductivity and high recombination rate of photogenerated electrons and holes limit its application in photocatalysis. In this work, we design and synthesize hierarchically porous zinc oxide/graphitic carbon nitride (ZnO/g-C 3 N 4) microspheres with type-II heterojunction to effectively degrade rhodamine B (RhB) via increasing the charge-separation efficiency. The ultraviolet-visible (UV–Vis) absorption spectra, Mott-Schottky plots and valence band X-ray photoelectron spectroscope confirm the formation of type-II heterojunction between ZnO nanocrystals and g-C 3 N 4 nanosheets. As a result, the 1.5-ZnO/g-C 3 N 4 composite (the mass ratio of zinc acetate dihydrate to g-C 3 N 4 is 1.5) exhibits the highest photocatalytic activity with good stability and higher photocatalytic degradation rate comparing to pure g-C 3 N 4 and pure ZnO. In addition, our results confirm that O 2 − and h+ are the main active species for ZnO/g-C 3 N 4 in degradation of RhB. [ABSTRACT FROM AUTHOR]

We report three types of conducting polymers (CPs), polyaniline (PANI), polypyrrole (PPY) and poly (3,4-ethylenedioxythiophene) (PEDOT) to modify the surface of the CdS nanorods to probe their photocorrosion inhibition and photocatalytic hydrogen production. Various characterizations, such as high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and density function theory (DFT) calculations have been conducted to reveal the intrinsic structure of the as-constructed CPs@CdS (@ means CPs at the surface of CdS) core-shell nanorods. The results show that the PANI and PPY shells with abundant N and C atoms can significantly enhance the binding energy of Cd and S atoms on the surface of the CdS nanorods. However, there is no obvious enhancement of binding energy at the interface of the PEDOT shell and the CdS nanorods core. Therefore, PANI@CdS and PPY@CdS possess stronger driving force than PEDOT@CdS to inject the photogenerated holes in conducting polymer shells. As a result, the polyaniline (PANI) modified PANI@CdS core-shell nanorods demonstrate the most effectively enhanced hydrogen production rate of ∼9.7 mmol h −1  g −1 and effective photocorrosion inhibition in 30 h without deactivation under visible-light irradiation. The hydrogen production performance of PPY@CdS is not effectively promoted owing to the weak transmittance of light for the PPY shell. The PEDOT shell cannot improve the hydrogen production and stability property of the CdS nanorods. This work could shed some light on conducting polymers modifying metal sulfides nanostructures that is of inconceivable significance for effective photocorrosion inhibition and highly enhanced photocatalytic activities. [ABSTRACT FROM AUTHOR]

Low stability and bioaccessibility are two unfavourable features that limit the application of many hydrophobic compounds. In this study, lecithin was complexed with polyvinylpyrrolidone K30 (PVPK30) to enhance the stability and bioaccessibility of curcumin via a precipitation-ultrasonication method. The curcumin-loaded nanocomplexes exhibited uniform sizes (∼120 nm), low polydispersity (∼0.22), and negative zeta potential (∼−45 mV). Curcumin was molecularly dispersed in lecithin-PVP complexes and exhibited an amorphous state. The curcumin-loaded nanocomplexes possess excellent dilution, thermal, and storage stability. More importantly, in vitro simulated gastrointestinal digestion experiment showed that the nanocomplexes could significantly improve the bioaccessibility of curcumin, reaching 105 times. Molecular dynamics simulation study revealed that lecithin and PVPK30 stabilized curcumin through hydrogen bonds, π-π interactions, and hydrophobic interactions. Our study provides a new way for curcumin and other hydrophobic compounds with excellent stability and bioaccessibility. • Lecithin and PVP shows excellent synergistic effect in stabilizing curcumin. • The binding behaviors of lecithin- PVP-curcumin nanocomplexes were revealed. • The nanocomplex increased the bioaccessibility of curcumin by 105 times. [ABSTRACT FROM AUTHOR]

Understanding molecular mechanisms of interactions between nanoparticles and bacteria is important and essential to develop nanotechnology for medical and environmental applications. Quantum dots (QDs) are specific nanoparticles with unique optical properties and high photochemical stability. In the present study, direct interactions were observed between cationic QDs and bacteria. Distinct fluorescence quenching patterns were developed when cationic QDs interacted with Gram negative and Gram positive bacteria. The aggregation of QDs on bacterial surface as well as fluorescence quenching depends upon the chemical composition and structure of the bacterial cell envelopes. The presence of lipopolysaccharide is unique to Gram-negative bacterial surface and provides negatively charge areas for absorbing cationic QDs. The effects of lipopolysaccharide were proved on fluorescence quenching of cationic QDs. In contrast to Gram-negative bacteria, the presence of teichoic acids is unique to Gram-positive bacterial cell wall and provides negatively charged sites for cationic QDs along the chain of teichoic-acid molecules, which may protect QDs from aggregation and fluorescence quenching. This study may not only provide insight into behaviors of QDs on bacterial cell surfaces but also open a new avenue for designing and applying QDs as biosensors in microbiology, medicine, and environmental science. [ABSTRACT FROM AUTHOR]

An efficient one-step process to synthesize highly porous (Ca-alginate–SiO 2 –polycation) shell: (Na-alginate–SiO 2 ) core hybrid beads for cell encapsulation, yielding a reusable long-life photosynthetically active material for a sustainable manufacture of high-value metabolites is presented. Bead formation is based on crosslinking of an alginate biopolymer and mineralisation of silicic acid in combination with a coacervation process between a polycation and the silica sol, forming a semi-permeable external membrane. The excellent mechanical strength and durability of the monodispersed beads and the control of their porosity and textural properties is achieved by tailoring the silica and alginate loading, polycation concentration and incubation time during coacervation. This process has led to the formation of a remarkably robust hybrid material that confers exceptional protection to live cells against sheer stresses and contamination in a diverse range of applications. Dunaliella tertiolecta encapsulated within this hybrid core–shell system display high photosynthetic activity over a long duration (>1 year). This sustainable biotechnology could find use in high value chemical harvests and biofuel cells to photosynthetic solar cells (energy transformation, electricity production, water splitting technologies). Furthermore the material can be engineered into various forms from spheres to variable thickness films, broadening its potential applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] A facile and fast refluxing method develops hierarchical and porous V2O5 spheres. [•] The porosity and morphology of vanadyl glycolate can be tuned by rinsing with water. [•] Hierarchical and porous V2O5 spheres possess high lithium ion storage property. [ABSTRACT FROM AUTHOR]

Highlights: [•] A fast microwave hydrothermal route is developed to prepare porous anatase spheres. [•] The TiO2 spheres are constructed of interconnected nanocrystals with wormlike pores. [•] The TiO2 spheres exhibit high Li ion storage capacity and good rate capability. [•] The Li ion storage property of TiO2 spheres varies with pore size and crystallinity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Highly ordered mesoporous silica thin films. [•] Control of mesoporous structure and mesochannels orientation. [•] A comprehensive revisit to synthesis parameters. [•] Wettability of different solvent and AFM study. [•] Pore size and surface area determined by Ellipsometry study. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous TiO2 with a hierarchically 3D dendrimeric nanostructure comprised of nanoribbon building units has been synthesized via a spontaneous self-formation process from various titanium alkoxides. These hierarchically 3D dendrimeric architectures can be obtained by a very facile, template-free method, by simply dropping a titanium butoxide precursor into methanol solution. The novel configuration of the mesoporous TiO2 nanostructure in nanoribbon building units yields a high surface area. The calcined samples show significantly enhanced photocatalytic activity and degradation rates owing to the mesoporosity and their improved crystallinity after calcination. Furthermore, the 3D dendrimeric architectures can be preserved after phase transformation from amorphous TiO2 to anatase or rutile, which occurs during calcination. In addition, the spontaneous self-formation process of mesoporous TiO2 with hierarchically 3D dendrimeric architectures from the hydrolysis and condensation reaction of titanium butoxide in methanol has been followed by in situ optical microscopy (OM), revealing the secret on the formation of hierarchically 3D dendrimeric nanostructures. Moreover, mesoporous TiO2 nanostructures with similar hierarchically 3D dendrimeric architectures can also be obtained using other titanium alkoxides. The porosities and nanostructures of the resultant products were characterized by SEM, TEM, XRD, and N2 adsorption–desorption measurements. The present work provides a facile and reproducible method for the synthesis of novel mesoporous TiO2 nanoarchitectures, which in turn could herald the fabrication of more efficient photocatalysts. [Copyright &y& Elsevier]

Abstract: Here, we supplied a direct and rapid quantum dots labelling method of bacterial cells in food, water and environmental contaminations. Outer layers of Escherichia coli cells prevent cells from direct interactions with molecules and objects such as quantum dots. Permeabilization treatment of E. coli cells may facilitate macromolecules penetrate cell walls and improve internal bacterial quantum dots (QDs) labelling. In this work, we investigated direct internal QDs labelling of E. coli cells permeabilized using three methods including chloroform-SDS treatment, lysozyme-EDTA treatment and osmotic shock treatment. Effects of permeabilization were analysed by scanning electronic microscopy and measuring activity of alkaline phosphatase (PhoA) released from periplasm. Internal bacterial QDs labelling was monitored by flow cytometry and fluorescent microscopy. After chloroform-SDS or lysozyme-EDTA treatment, cells could be directly labelled with QDs. No interaction was observed between osmotic shock treated cells and QDs. The mechanism of cell permeabilization explaining different labelling efficiency has been established. The QDs labelling approach presented in this work provides a simple, rapid and sensitive detection method for multiple purpose bacterial analysis in combination with biological techniques. [Copyright &y& Elsevier]

Abstract: We report on one-pot synthesis of various morphologies of CuO nanostructures. PEG200 as a structure directing reagent under the synergism of alkalinity by hydrothermal method has been employed to tailor the morphology of CuO nanostructures. The CuO products have been characterized by XRD, SEM, and TEM. The morphologies of the CuO nanostructures can be tuned from 1D (nanoseeds, nanoribbons) to 2D (nanoleaves) and to 3D (shuttle-like, shrimp-like, and nanoflowers) by changing the volume of PEG200 and the alkalinity in the reaction system. At neutral and relatively low alkalinity (OH−/Cu2+ ≤3), the addition of PEG200 can strongly influence the morphologies of the CuO nanostructures. At high alkalinity (OH−/Cu2+ ≥4), PEG200 has no influence on the morphology of the CuO nanostructure. The different morphologies of the CuO nanostructures have been used for the photodecomposition of the pollutant rhodamine B (RhB) in water. The photocatalytic activity has been correlated with the different nanostructures of CuO. The 1D CuO nanoribbons exhibit the best performance on the RhB photodecomposition because of the exposed high surface energy {−121} crystal plane. The photocatalytic results show that the high energy surface planes of the CuO nanostructures mostly affect the photocatalytic activity rather than the morphology of the CuO nanostructures. Our synthesis method also shows it is possible to control the morphologies of nanostructures in a simple way. [Copyright &y& Elsevier]

Abstract: Anchored periplasmic expression (APEx) technology aims to express and localize proteins or peptides in the Escherichia coli periplasm. Some reports have suggested that transmembrane segments of integral membrane proteins can be used as membrane anchors in the APEx system. In this study, a series of hydrophobic anchors derived from the first putative transmembrane helix of a Bacillus subtilis integral membrane protein, MrpF, and its truncated forms were investigated for anchored periplasmic expression of alkaline phosphatase (PhoA) in E. coli. Anchoring efficiency of hydrophobic anchors was evaluated by monitoring the expression and activity of anchored PhoA. The length of hydrophobic anchors was found to be critical for anchoring proteins to cell membranes. This study may open new avenues for applying transmembrane segments derived from native membrane proteins as membrane anchors in the APEx system. [Copyright &y& Elsevier]

Abstract: Hierarchical porous architecture with interconnected trimodal micro-meso-macroporous systems constructed from uniform zeolite Zr-doped silicalite-1 nanocrystals has been prepared. The synthesis has been made by using glycerin as a reaction medium via a quasi-solid-state crystallization of hierarchically meso-macroporous zirconosilicate precursor under the effect of the structure directing agent TPAOH. The presence of glycerin is crucial in the synthesis systems to maintain the porous hierarchy. The pores inter-connectivity, Zr location in the framework, the acidity and the catalytic activity have been studied by laser-hyperpolarized 129Xe NMR spectroscopy, UV–visible spectroscopy, temperature-programmed desorption of ammonia and the catalytic isopropylbenzene cracking probe reaction, respectively. The products possess well-defined macrochannels interconnected with mesopores located in the macropore walls, which in turn have been constructed from microporous MFI-type zeolite units. 129Xe NMR study indicated that the hierarchically micro-, meso-, macro-pore systems are homogeneously distributed throughout the final materials and well interconnected, which is important for molecular diffusion. The TPD-NH3 investigation revealed that the hierarchically micro-meso-macroporous materials constructed from zeolite Zr-Silicalite-1 nanocrystals present strong acidity. [Copyright &y& Elsevier]

Abstract: Various hierarchical porous titania with high surface area over 600m2/g have been synthesized via a spontaneous self-formation process from titanium alkoxides by a water adjusting approach using acetonitrile as reaction medium. The reactivity of metal alkoxides and the water content in acetonitrile medium on the resultant structure have been investigated. The porosities of the products were characterized by SEM, TEM and N2 adsorption–desorption measurements. The observation on the evolution of porous structure with increasing water content in reaction system is essential for a better understanding of hierarchical porous structure formation over different length scales by this self-formation process. The creation of macro/micropores in photocatalytic titania materials has been found to enhance the photocatalytic activity due to both the action of macrochannels as light harvester and the easy diffusion effect of organic molecules. The present work shows clearly that hierarchically porous titania with the presence of macroporous structure and high surface area can be very efficient photocatalysts, suggesting their potential applications in water treatment as decontamination materials. [Copyright &y& Elsevier]

Abstract: A simple synthesis pathway has been developed for the design of hierarchically structured spongy or spherical voids assembled meso-macroporous aluminosilicates with high tetrahedral aluminium content on the basis of the aqueous polymerisation of new stabilized alkoxy-bridged single molecular precursors. The intimate mixing of an aluminosilicate ester (sec-BuO)2–Al–O–Si(OEt)3 and a silica co-reactant (tetramethoxysilane, TMOS) with variable ratios and the use of alkaline solutions (pH 13.0 and 13.5) improve significantly the heterocondensation rates between the highly reactive aluminium alkoxide part of the single precursor and added silica co-reactant, leading to aluminosilicate materials with high intra-framework aluminium content and low Si/Al ratios. The spherically-shaped meso-macroporosity was spontaneously generated by the release of high amount of liquid by-products (water/alcohol molecules) produced during the rapid hydrolysis and condensation processes of this double alkoxide and the TMOS co-reactant. It has been observed that both pH value and Al–Si/TMOS molar ratio can strongly affect the macroporous structure formation. Increasing pH value, even slightly from 13 to 13.5, can significantly favour the incorporation of Al atoms in tetrahedral position of the framework. After the total ionic exchange of Na+ compensating cations, catalytic tests of obtained materials were realised in the esterification reaction of high free fatty acid (FFA) oils, showing their higher catalytic activity compared to commercial Bentonite clay, and their potential applications as catalyst supports in acid catalysed reactions. [Copyright &y& Elsevier]

Abstract: Mesoporous metal oxides (CeO2−δ)–YSZ have been synthesized by a versatile direct synthesis method using ionic cetyltrimethylammonium bromide (CTAB) and different nonionic (block copolymers) as surfactants and urea as hydrolyzing agent. The synthesis was realized at pH=9 using tetraethylammonium hydroxide (TEAOH) as pH mediator. Calcination at 550°C led to the formation of crystalline metal oxides with uniform mesoporosity. The obtained materials have been characterized by thermogravimetric analysis (TG-DTG), wide and small-angle X-ray diffraction (XRD), Raman spectroscopy, Brunauer, Emmett and Teller (BET) surface area analysis, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). All the obtained materials exhibits mesoporous structure, crystalline structure indexed in a cubic symmetry, showing a high surface area, a uniform and narrow pore size distribution, spherical morphology typical for the mesoporous materials. The crystalline and mesoporous structures, surface chemistry and stoichiometry for the samples synthesized using ionic and nonionic surfactants have been discussed. [Copyright &y& Elsevier]

Abstract: Over the past few years the idea of living photosynthetic materials has advanced from concept to reality. This work outlines the improvements made in the immobilisation of the thermotolerant acidophile Cyanidium caldarium (Tilden) Geitler SAG 16.91 within porous and transparent silica gels with the view to targeting photochemical materials that can be used to mitigate rising CO2 emissions. Our results suggest that the immobilised cells are autofluorescent for at least 75days post encapsulation and can maintain a steady oxygen production rate over a similar timeframe corroborating the viability and physiological activity of silica immobilised C. caldarium. [Copyright &y& Elsevier]

Abstract: Ultralong Cu(OH)2 and CuO nanowire bundles with lengths ranging from tens to hundreds of micrometers have been selectively synthesized on a large scale by a facile solution-phase method, using PEG200 as growth-directing agent. The growth mechanisms were investigated by monitoring the nanowire evolution process. The results showed that under the action of PEG200 molecules, the Cu(OH)2 and CuO nanowires were first formed through oriented attachment of colloidal particles, then through side self-assembly leading to nanowire bundles, and finally to CuO nanoleaves. PEG200 plays a critical role in the synthesis of nanowires as it not only prevents the random aggregation of colloidal particles toward CuO nanoleaves but also helps to orientate nanowire growth by the coalescence and alignment in one direction of the colloidal particles. The concentration of OH− in the reaction system is also important for nanowire growth. In the absence of PEG200, nanoleaves are formed by an Ostwald ripening process. The band-gap value estimated from a UV–Vis absorption spectrum of CuO nanowire bundles is 2.32eV. The photodegradation of a model pollutant, rhodamine B, by CuO nanowires and nanoleaves was compared with commercial nanopowders, showing that the as-synthesized ultralong CuO polycrystalline nanowire bundles have an enhanced photocatalytic activity with 87% decomposition of rhodamine B after an 8-h reaction, which was much higher than that of single-crystal nanoleaves (61%) and commercial nanopowders (32%). The origin of the high photocatalytic activity of these new polycrystalline CuO nanowire bundles has been discussed. This present work reveals that the (002) crystallographic surface is more favorable for photocatalytic decomposition of organic compounds and that these ultralong CuO nanowire bundles are potential candidates for photocatalysts in wastewater treatment. [Copyright &y& Elsevier]

Abstract: Highly organized rutile Titania inverse opal-based photonic crystals that exhibit reflective properties in the UV–Visible range have been constructed. A self-assembly method was employed to infiltrate the interstitial space of a highly organized polymeric opal with a titania alkoxide precursor under well controlled conditions. Further hydrolysis and drying steps led to the formation of polystyrene spheres/amorphous TiO2 opaline nanocomposites which exhibited very interesting optical properties with a photonic bandgap (PBG) in the infrared range. The TiO2 inverted opal was subsequently obtained by the removal of the template either by chemical dissolution or calcination. The latter method was shown to yield samples of high quality and the influence of the calcination temperature on photonic crystal properties was studied by XRD, FESEM, EDX and Reflectance measurements. The highly organized, dense and thermally stable TiO2 inverse opal obtained through calcination shows low defect density and a sharp reflection of incident UV–Vis–NIR light at around 380nm and is then expected to possess a complete photonic bandgap due to the highly refringent dense rutile phase and the controlled and small lattice parameters of the crystal. The crystalline phase, the structural properties and the excellent thermal stability of the material (up to 1000°C) are discussed. [Copyright &y& Elsevier]

Abstract: Cyanidium caldarium (Tilden) Geitler SAG 16.91 has been encapsulated within a porous silica host structure to target novel photosynthetic hybrid materials suitable for use in solar cells or CO2 fixation. C. caldarium cells are both thermophilic and acidophilic; on account of these tolerances the hybrid materials could be employed in more extreme heat conditions. TEM highlights that the external cell membrane can remain intact after encapsulation. The images reveal an alignment of silica gel around the external membrane of the cell, providing evidence that the cell wall acts as both a nucleation and polymerisation site for silica species and that the silica scaffold formed by the aggregation of colloidal particles, generates a porosity that can facilitate the transport of nutrients towards the cell. Epifluorescence microscopy and UV–visible spectroscopy have revealed the preservation of photosynthetic apparatus post-immobilisation. Productivity studies showed how the presence of silica nanoparticles within the matrix can adversely interact with the exterior cellular structures preventing the production of oxygen through photosynthesis. [Copyright &y& Elsevier]

Abstract: The catalytic conversion of chloromethane over HSAPO-34 was followed by in situ Fourier transform infrared (FTIR) spectroscopy and catalytic testing. Our detailed IR investigation allowed the identification of the active sites and the adsorbed species. HSAPO-34 has high activity and selectivity for the production of light olefins. The FTIR results demonstrated that the conversion starts at 350 °C with the formation of alkoxy groups as intermediate products. On adsorption and conversion of chloromethane, three distinct shifts of associated with the Si(OH)Al acidic sites were observed, attributed to the interaction between Si(OH)Al with CH3Cl, HCl and C In the 350–500 °C temperature range, chloromethane is converted to ethylene, propylene, and butylenes with 70–80% selectivity. Increasing reaction temperature increases conversion and enhances the yield of lighter olefins. The detailed FTIR study of chloromethane conversion at 450 °C at different system chloromethane loadings reveals that increasing system CH3Cl loading increased the conversion rate. This is attributed to the participation of gas-phase chloromethane molecules with adsorbed species enhancing the reaction rate, while at lower chloromethane loadings, the reactions may just occur between the adsorbed species. The IR studies also reveal the reversible breaking of Alh name="sbnd" />P bonds on adsorption of HCl, a main product of the reaction, to generate large amounts of P. The Alh name="sbnd" />P bonding was restored after removal of HCl by evacuation at 150 °C. These IR observations combined with the catalytic test results allow us to propose a realistic reaction mechanism. [Copyright &y& Elsevier]