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• A series of NH 2 -MIL-125-Ni 0.5-1.5% /Ti photocatalysts are in situ synthesized. • The prepared NH 2 -MIL-125-Ni 0.5-1.5% /Ti exhibits enhanced CO 2 reduction activity. • The electronic structure of (Ti/Ni) 8 O 8 (OH) 4 nodes has effect on MOF's band structure. • The Ni2+ induced electronic structure change of (Ti/Ni) 8 O 8 (OH) 4 nodes are analyzed. • The Ni2+ dopants sites are discussed based on the electrostatic potential analysis. Regulation of the electronic structure of metal oxo clusters in metal organic frameworks (MOFs) is a promising way to modulate charge transfer efficiency and photocatalytic performance. Herein, a series of Ni2+ doped NH 2 -MIL-125-Ti (NH 2 -MIL-125-Ni x /Ti) with different Ni2+/Ti4+ molar ratio (x = 0.5%–1.5%) are prepared via an in-situ doping method. Correlations between the electronic structure of (Ti/Ni) 8 O 8 (OH) 4 nodes and charge transfer efficiency, bandgap and energy position of band edges of the NH 2 -MIL-125-Ni x /Ti are systematically investigated based on experimental and computational method. The doped Ni2+ was confirmed to be an efficient mediator to promote the electron transfer from photoexcited terephthalate ligand to the (Ti/Ni) 8 O 8 (OH) 4 nodes in NH 2 -MIL-125-Ni x /Ti. The NH 2 -MIL-125-Ni 1% /Ti exhibited the highest CO 2 conversion rate with 98.6% CO selectivity and the factors affecting the photocatalytic CO 2 reduction performance are also studied. It provides some guidance for developing MOFs photocatalyst with targeted performance via modification of the electronic structure of metal oxo clusters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel titanium-containing precursors was used to prepare hierarchical TS-1. • The mesopore volume and framework Ti contents were enhanced due to diphenolics. • The conversion and selectivity in 1-hexene epoxidation was greatly improved. Hierarchical TS-1 zeolites with high catalytic activities toward 1-hexene epoxidation were successfully synthesized by using novel titanium-containing precursors. The precursors were prepared by o / m / p -dihydroxybenzene with tetrabutyl titanate, which not only promote the uniform distribution of titanium sources and reduce the aggregation of Ti species, but also contribute to regulating the coordination state of Ti species and increasing the frameworks Ti contents. TS- m / p -DHB-48h zeolites display excellent catalytic performance in the epoxidation reaction of 1-hexene, and the conversion improved by 41.9 % and 34.7 %, respectively. The hierarchical zeolites also exhibit superior 1,2-epoxyhexane selectivity, which will greatly improve the efficiency of industrial production. [ABSTRACT FROM AUTHOR]

Highly dispersed Pt NCs using the SMSI effect was anchored in UiO-66 type mesoporous Ce-PyDC MOF containing pyridine N and OMS. Pyridine N and the OMS modulate the SMSI effect by altering the electron cloud density and microchemical environment of Pt, resulting in efficient low temperature DCPD hydrogenation. [Display omitted] • A mesoporous Ce-PyDC MOFs with abundant pyridine N sites and OMS were constructed. • The SMSI effect between Ce-PyDC and Pt was regulated by pyridine N and OMS. • Highly dispersed Pt nanoclusters and optimized d-band center promote the H 2 adsorption/dissociation and DCPD hydrogenation. • The Pt NCs@Ce-PyDC can efficiently convert DCPD to THDCPD at a low temperature. Strong metal-support interaction (SMSI) plays an important role in heterogeneous catalysis, but the influence of the chemical microenvironment of metal on it is often neglected. In this study, a mesoporous Ce-MOFs with pyridine N sites and open metal sites (OMS) were constructed, and highly dispersed Pt nanoclusters (NCs) and Pt-N x interface were subsequently introduced and constructed via SMSI effect for hydrogenation of dicyclopentadiene (DCPD). The spectroscopic results and density functional theory (DFT) computations demonstrate that pyridine N and OMS can regulate the SMSI effect between Ce-PyDC and Pt through Pt-N x interface and electronic interaction between Pt and OMS, which increase electron cloud density of Pt nanoclusters, promote DCPD adsorption, H 2 activation. The optimal Pt NCs@Ce-PyDC-3 can efficiently convert DCPD to tetrahydrodicyclopentadiene (THDCPD) at 50 °C, giving a 100 % DCPD conversion and 99 % THDCPD selectivity. This work provides an in-depth understanding of the correlation between the metal nanoparticle microenvironment and SISM effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • The influencing factors of MOFs for CO 2 capture and CO 2 -to-alcohols are discussed. • Strategies for improving the CO 2 capture of MOFs-based materials are introduced. • The catalytic systems used for CO 2 -to-alcohols are summarized. • The hydrogenation pathway of CO 2 -to-alcohols by MOFs-based materials are presented. • The challenges and trends of MOFs in CO 2 capture and conversion are prospected. The global climate change caused by the continuous increase of carbon dioxide (CO 2) emissions has seriously threatened the survival of human beings, so it is imperative to control its emission reduction and achieve its utilization. The adsorption of CO 2 and conversion into high-value-added chemicals can not only reduce the exhaust emission of greenhouse gas, but also help to solve the problems of excessive dependence on fossil fuels and the storage of renewable energy. As a promising carbon recycling technology, carbon capture and utilization (CCU) has attracted wide attention in the past decades. Various functional materials such as metal-organic frameworks (MOFs), metal oxides, molecular sieves and porous carbon materials have sprung up for CO 2 capture and conversion. MOFs have become a more promising candidate due to their highly tunable pore structure, easy surface functionalization and abundant active sites. This paper reviews most studies published in the last five years on MOFs used for capturing CO 2 and CO 2 -to-alcohols conversion. The main topics include 1) The influencing factors of MOFs-based materials for CO 2 capture and CO 2 -to-alcohols; 2) strategies to improve CO 2 adsorption performance and the role of high throughput computational screening (HTCS) on the development and screening of MOFs adsorbent; 3) MOFs-based materials used for CO 2 -to-alcohols conversion in photo-, electro-, thermal-catalytic and their hybrid catalytic systems, as well as the corresponding mechanistic studies. The purpose of this review is to offer a technical and theoretical direction for the creation and industrial implementation of high-performance MOFs-based materials in the field of CO 2 adsorption and conversion, highlight the associated challenges and opportunities. [ABSTRACT FROM AUTHOR]

Encapsulation of TiO 2 nanobelts into crystalline and porous covalent organic frameworks materials to form a core-shell structure can enhance reactivity, selectivity and durability of photocatalysts distinctly. In this work, a range of TiO 2 nanobelts@COF nanocomposites with different thicknesses of COF shell were fabricated via a novel and facile seed growth method. The results of photooxidation of benzyl alcohol under visible light (> 420 nm) showed that TiO 2 @COF-3 with COF shell thickness of around 15 nm showed the highest conversion (92.5%) with the maximum rate constant (6.73 × 10−2 h−1), which is approximately 10.1 times as that of TiO 2 and 12.9 times as that of COF. The enhanced photocatalytic activity of hybrid materials was mainly owing to the improved photon adsorption ability and charge carriers transfer from COF to TiO 2. In addition, TiO 2 @COF-3 still showed relatively high stability after 5 cycles under the same reaction condition. Therefore, this type of hybrid photocatalysts possesses great potentials in future green organic synthesis. • Core-shell TiO 2 @COF hybrids are synthesized by a seed growth method. • The COFs materials show as an excellent light-harvest materials. • The covalent-bond connection promotes the charge-carrier transfer and separation. • TiO 2 @COF-3 shows high activity and stability in photooxidation of aromatic alcohols. • TiO 2 @COF hybrids are firstly applied to the photooxidation of aromatic alcohol. [ABSTRACT FROM AUTHOR]

Promoting photo-induced electron transfer is one of the most efficient approaches for improving photocatalytic hydrogen production performance. Herein, we construct a novel interfacial lateral electron migration path by introducing CoP 2 into CdS photocatalytic system as cocatalyst for the first time. This peculiar migration path can be attributed to two aspects: 1) the built-in electric field between CoP 2 and CdS could drive carrier separation effectively; 2) the "metallized" interface serves as a special electron trap to accumulate electrons and promote them transfer along it instead of diffusion into cocatalyst. The energy-efficient interface shortens the electron migration distance and make more hot electrons participate in the reaction at the active sites with lower activation energy. As expected, the optimal hydrogen production rate of CoP 2 /CdS reaches up to 1071 mmol h−1 g−1, which is one of the most robust photocatalytic hydrogen production systems. [Display omitted] • A series of CoP x /CdS with different Co-P ratios were simply synthesized by modulating the ratio of Co and P sources. • A novel interface consisting of a built-in electric field region and a "metallized" region is constructed. • The special interface effectively traps photogenerated electrons and makes more hot electrons be used efficiently. • The optimal photocatalytic performance of CoP 2 /CdS was up to 1071 mmol h−1 g−1. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The recent efforts concerning porous ss-PCMs were reviewed. • The effects of different porous materials on the phase change behaviors of ss-PCMs are discussed. • This review will lead to a better understanding on the designing and constructing of efficient ss-PCMs. Abstract Phase change materials (PCMs) are widely utilized in latent thermal energy storage and thermal management systems due to their high-energy storage density, high latent heats and excellent capabilities of maintaining almost constant temperature. However, the formidable challenge still seriously limited the performance of PCMs in thermal energy storage systems, such as their leakage and low thermal conductivities. Therefore, appropriate approaches to construct shape-stabilized PCMs (ss-PCMs) and effectively enhance the thermal conductivities are importantly necessary to realize the practical applications of PCMs. Porous supports packaged PCMs provide an effective route for constructing ss-PCMs with enhanced thermal conductivity, mechanical strength, chemical stability and flame resistance. In this review, we aim to assess the advantages/disadvantages of porous materials via summarizing the key research progress on the porous materials (e.g., metal foams, expanded graphite, graphene aerogels, carbon nanotubes, porous minerals, mesoporous silica, etc.) as ss-PCMs supports. The effects of pore size and geometry, surface modification, interaction forces, compositions, etc. on the phase change behaviors of ss-PCMs are summarized and discussed in detail by comparing the different porous materials. We believe that the summary and discussion in the review will lead to a better understanding on the designing and constructing of efficient ss-PCMs, and even shed light on the design for novel porous materials supported ss-PCMs based on the discovered interactions between the porous supports and PCMs. Finally, the future research topics and challenges on porous materials for ss-PCMs development are also prospected with emphasizing on the emergence of new design of porous materials with improved thermal conductivity, high PCMs loading amount and high thermal latent for practical applications. [ABSTRACT FROM AUTHOR]

New shape‐stabilized paraffin/porous carbon materials derived from metal organic gel (cMOG)/boron nitride (BN) composites were prepared by the impregnation method. In the composites, paraffin was used as phase change material, while cMOG as a supporting and loading large paraffin content in the pores owing to high specific surface area and BN employed to enhance the thermal conductivity. The scanning electron microscopy images showed better filler–filler connectivity in BN/cMOG than the individual supporting materials. With the synergy of BN and cMOG, the thermal conductivity of BN/cMOG/PCM composites exhibited up to 232.1 % of pristine PCM and 82.3 % of binary BN/PCM composites at the same wt.‐% of BN. The latent heat as‐synthesized composite attains up to 163.1 J/g with up to 80 wt.‐% of paraffin retained in the composites without any leakage. In addition, the composites revealed enhanced heat transfer performance in both the solid and liquid states. Similarly, the XRD and FTIR analysis showed excellent chemical compatibility between paraffin and the supporting materials. In addition, the composite has high thermal stability, reduced supercooling extent, and better reliability after 200 times thermal cycling, which indicate a promising method for large‐scale thermal energy storage. Shape‐stabilized porous carbon materials derived from metal organic gel/BN/paraffin were prepared. They have enhanced heat transfer performance in both the solid and liquid phases and large energy storage capacity. [ABSTRACT FROM AUTHOR]

Hollow porous Fe2O3 hexagonal nanorods were fabricated via a facile and controllable approach using MOFs (Fe-MIL-88A) as both precursors and sacrificial templates. It has been found that Fe(OH)3, which is formed on the surface of MOFs after treatment with NaOH solution, plays a significant role in maintaining its morphology during calcination. The interior of well-defined hollow porous Fe2O3 hexagonal nanorod structures is assembled by interconnected nanoparticles to form a porous structure. As anode materials for Li-ion batteries, the hollow porous Fe2O3 hexagonal nanorods exhibit long-term cycling stability (1219 mA h g−1 after 100 cycles) and ultrahigh rate capability. The high electrochemical performance is attributed to the unique structure and morphology of the hollow porous nanorods. [ABSTRACT FROM AUTHOR]

• Structure-activity relationship of 16 MOFs were discussed for SADS. • Stability of MOFs dependent by coordination environment of their metal cations. • Binding strength of Cu-S bond is revealed by theoretical simulation. Cu-based metal organic frameworks (MOFs) are promising adsorbents for the selective adsorption desulfurization (SADS) towards mercaptans in fossil fuels, while the structural collapse problem restricts their application due to the strong interaction between the copper cations and mercaptans. To find a solution, the factors mattering to the SADS ability of MOFs are comprehensively discussed by comparing the structure–activity relationship of 16 MOFs. Especially, the influence of topology, structure of second building unit (SBU) and coordination environment of metal cations of these MOFs are investigated. The experimental results indicate that the binding strength between copper cations and mercaptan is mainly dependent by the coordination environment of the copper cations. And a MOF, ADODAA with copper cations squarely coordinated with two oxygen and two nitrogen atoms exhibits significantly higher stability and renewability over other Cu-based MOFs whose copper cations only coordinates with four oxygen or nitrogen atoms, due to its moderate binding strength towards mercaptan. This work unravels the strong dependence of the stability of MOFs on the coordination environment of its metal cations and provides a platform for constructing highly stable SADS adsorbents. [ABSTRACT FROM AUTHOR]

Light-driven, improved thermal conductivity and effective phase change enthalpy of polymeric composite material was prepared by one-pot synthesis approach based on the introduction of chromophoric polymer phase change material in nitrogen-doped porous carbon (NPC). Various characterization techniques were employed to investigate the thermal and structural properties of as-synthesized samples. The composite exhibited a light-to-heat conversion capacity of 72.1% owing to the introduction of environmental friendly and commercially available functional dye molecule in the polymer matrix. In addition, the composite achieved large energy storage efficiency per unit mass up to 180.3 J/g with high crystallinity, close to the maximum value since then documented for cross-linked polymeric composites, as well the composite achieving a thermal conductivity up to 178.3% with low porous carbon addition. The superior thermal storage performance could be ascribed to the advantages of NPC porous structure and interaction with hard segment results free phase change materials (PCMs) in a certain degree and used for high energy storage efficiency. Likewise, the composite revealed stable thermal performance with time saving strategy. This investigation gives an outlook for the synergistic improvement of thermal conductivity, solar-to-heat conversion capacity and latent heat of solid-solid PCMs. [ABSTRACT FROM AUTHOR]

Energy storage capacity and heat transfer ability are two important indexes for shape-stabilized phase change materials (ss-PCMs). In this paper, a core-sheath CNT@PC was prepared via carbonation of CNT@ZIF-8, simultaneously 3D structural supports were obtained due to the porous carbon (PC) sheath stabilized the CNT@PC network structure. Porous carbon (PC), derived from carbonized metal organic frameworks (MOFs), exhibited high porosity and large specific surface area. PCMs, absorbed by capillary force of porous structure, was stabilized in the pores of PC sheath. Further, the interaction between PCMs and CNTs reduced the interfacial thermal resistance greatly. Carbon nanotubes (CNTs), acting as heat transfer pathways, provided continuous channels for phonons transfer and realized rapid heat transformation between ss-PCMs and external environment. The obtained SA/CNT@PC ss-PCMs exhibited excellent thermal conductivity (1.023 W/mK), large phase change enthepy (155.7 J g −1 ) and high thermal storage capabilities (99.9%). The thermal conductivity of SA/CNT@PC was improved 222.6% and phase change enthalpy was increased 92.6% over SA/PC ss-PCM. SA/CNT@PC with large energy storage density, flexible designation, simple operation and near-constant temperature properties during phase change process shows great potential in waste heat utilization. [ABSTRACT FROM AUTHOR]

A novel in-situ assembly strategy has been developed to synthesis polyethylene glycol (PEG)@iron-benzenetricarboxylate metal-organic gel (MOG-100-Fe) shape-stabilized composite phase change materials by regulating metal-to-ligand ratio. The PEG@MOG-100-Fe was prepared by an ingenious introduction of PEG into the traditional sol-gel prepared MOG-100-Fe. The composite exhibited high heat storage density and thermal stability. The PEG loading content reached up to 92% without any leakage above its melting point. The heat storage density reaches to 152.88  kJ   kg −1 and is up to 95.8% of their theoretical value. These novel composite PCMs also exhibited excellent recyclability after 50 thermal cycles. [ABSTRACT FROM AUTHOR]

A systematic mesoporous N-doped carbons/myristic acid-stearic acid composite materials with improved thermal conductivity, energy storage density and shape stable performance were prepared by encapsulating myristic acid-stearic acids (MA-SA) eutectic mixture into porous carbon matrixes derived from two synthesis strategies. The effect of synthesis strategies and the N species present in porous carbons on the microstructure and thermal energy storage properties of composite phase change materials were studied by various characterization techniques. The results indicated that N-doped porous carbons derived from in situ (NPC) had maximum of up to 88 wt% PCM loading with a melting latent heat of 164.33 ± 0.29 kJ/kg, which was up to 45.69% higher than that of composite PCMs by post synthesis route (MGC/MA-SA). Factors, like pore characteristics, capillary force, surface tension and additional interaction with N species present in carbon matrix played vital roles for encapsulation of MA-SA to the pores of supporting materials. Notably, NPC/MA-SA composite materials exhibited excellent thermal conductivity, 117.65% higher than pristine PCM, while 74.59% for MGC/MA-SA. The content, homogeneous distribution and graphitic nature of N as well as the interconnected porous carbons improves the heat transfer pathways in the composite PCMs during phase change process. All the prepared samples were thermally and chemically compatible even after 100 times thermal cycling, confirming that the prepared composite materials were a promising candidates for thermal management system in a medium phase transition temperatures like domestic solar hot water supply and air-conditioning purposes. [ABSTRACT FROM AUTHOR]

Developing efficient non-noble metal and earth-abundant electrocatalysts with tunable microstructures for overall water splitting is critical to promote clean energy technologies for a hydrogen economy. Herein, novel three-dimensional (3D) flower-like Ni2P composed of mesoporous nanoplates with controllable morphology and high surface area was prepared by a hydrothermal method and low-temperature phosphidation as efficient electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the urchin-like Ni xP y, the 3D flower-like Ni2P with a diameter of 5 μm presented an efficient and stable catalytic performance in 0.5 m H2SO4, with a small Tafel slope of 79 mV dec−1 and an overpotential of about 240 mV at a current density of 10 mA cm−2 with a mass loading density of 0.283 mg cm−2. In addition, the catalyst also exhibited a remarkable performance for the OER in 1.0 m KOH electrolyte, with an overpotential of 320 mV to reach a current density of 10 mA cm−2 and a small Tafel slope of 72 mV dec−1. The excellent catalytic performance of the as-prepared Ni2P may be ascribed to its novel 3D morphology with unique mesoporous structure. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF)-based mixed matrix membranes (MMMs) were fabricated by a combination of Cu3(BTC)2 MOF and polymer cellulose acetate. The cellulose acetate in the MMMs served as the matrix and the Cu3(BTC)2 MOF as the filler. The as-synthesized MMMs were utilized as a heterogeneous catalyst for aldehyde acetalization. The characterization techniques indicated that the Cu3(BTC)2 crystals were uniformly dispersed in the MMMs. The BET surface area of the Cu3(BTC)2-based MMM was measured to be 459 m2 g−1 at 60 wt% Cu3(BTC)2 loading. Furthermore, the MMMs served as an excellent catalyst under our continuous flow catalytic reaction conditions. The optimal catalytic result of benzaldehyde yield reached 94% with 60 wt% Cu3(BTC)2 loading of the MMMs at room temperature and the benzaldehyde diethyl acetal reached 0.59 mmol min−1 gCu-BTC−1. [ABSTRACT FROM AUTHOR]

Toluene oxidation behavior has been investigated on a series of catalysts with Pt supported on MCM-48 that has a large specific surface area & easy-transported three-dimensional channels prepared by four different methods. It was found that various introduction ways of Pt have a great influence on both Pt content and state, resulting in a difference in catalytic oxidation performance. Pt/M48-PG prepared via the post-grafting method possesses both the highest Pt content (0.83 wt%) and active species of Pt0 & surface labile oxygen (accounting for 46% and 55%, respectively), resulting in the lowest T 90 (155 °C) and the highest TOF (7.92 ×10−3·s−1). Characterization results showed that the amine functional groups could be successfully grafted onto the support's surface, which is beneficial for the binding of platinum precursor with support, leading to the high actual loading efficiency and dispersion of Pt, both of which contribute to retaining more Pt0 and surface labile oxygen active species. [Display omitted] • Evolution on Pt/MCM-48′s property by different preparation methods is discussed. • The usage efficiency of Pt was significantly increased by post-grafting method. • The post-grafting method enhanced the catalyst's capacity for Pt0 retention. • Discussion over the connection among Pt0, reactive oxygen and catalytic performance. [ABSTRACT FROM AUTHOR]

• PCN-222/CsPbBr 3 was fabricated by an electrostatic self-assembly method. • PCN-222/CsPbBr 3 exhibits enhanced visible-light photocatalytic activity in CO 2 -to-HCOOH conversion. • The Z-Scheme heterojunction is responsible for the photocatalytic improvement. • The mechanism of the photocatalytic CO 2 RR over PCN-222/CsPbBr 3 is proposed. Exploring photocatalysts with efficient charge separation to boost CO 2 reduction to valuable chemicals is of great significance. Herein, we develop a PCN-222/CsPbBr 3 hybrid with direct Z-scheme heterojunction for high-efficiency photoreduction of CO 2 to HCOOH. By delicately controlling the interface of the PCN-222/CsPbBr 3 hybrid, effective electron transfer from CsPbBr 3 to PCN-222 is achieved, leading to the construction of an internal electric field (IEF). The photo-induced electrons transfer from PCN-222 to CsPbBr 3 under visible light irradiation derived from IEF is confirmed by in-situ X-ray photoelectron spectroscopy (XPS), transient absorption (TA), and Kelvin probe force microscopy (KPFM), resulting in the impactful spatial separation of electron-hole pairs. The optimized PCN-222/CsPbBr 3 catalyst with direct Z-scheme heterojunction finally offers a 7.0- and 2.1-times enhancement in CO 2 photoreduction to HCOOH compared to pristine PCN-222 and CsPbBr 3 , respectively. This work provides a facile strategy for developing superior perovskite-based CO 2 RR photocatalysts with both high catalytic activity and selectivity of value-added products. [ABSTRACT FROM AUTHOR]

• ADS performance of the best CuBDC-x is 104.5% higher than the original CuBDC. • Both the defects and porosity can be regulated by a defect engineering method. • A convenient ethanol thermal treatment is developed to reduce Cu2+ to Cu+. • Cu+ rather than Cu2+ are demonstrated to be the adsorption site of mercaptan. Adsorption desulfurization (ADS) is one of the most potential technologies for desulfurization of gasoline, while developing adsorbents with high sulfur capture capability to meet the strict environmental regulations remains a challenge. Here, a series of CuBDC-x adsorbents containing additional defects and enhanced adsorption sites via modulator-induced defect engineering and subsequent post-synthetic reduction strategy were synthesized. The optimal CuBDC-1 samples showed a remarkable sulfur adsorption capacity of 41.1 mg S/g in model fuel, which is 104.5 % higher than that of original CuBDC. The Cu+ rather than Cu2+ cations in MOFs were found to be the main adsorption sites for mercaptan molecules. This work offers a new insight into developing high-efficiency adsorbent for ultra-deep desulfurization. [ABSTRACT FROM AUTHOR]

Hierarchical heterostructures with specific compositions, morphology and functionalities are important for applications in many fields such as catalysis, energy storage and conversion. Herein, hierarchical sandwich-like heterostructures were prepared by a self-assembly method of growing MIL-100(Fe) on host two dimensional (2D) TiO 2 nanosheets (TiO 2 NS). The introduction of porous MIL-100(Fe) on TiO 2 NS improves the adsorption ability of nanocomposites owing to the porous tunnel adsorbing organic molecules and high surface area. In addition, the interfaces of TiO 2 NS and MIL-100(Fe) provide platforms for rapid photoexcited electrons transfer and enhance the photocatalytic activity of TiO 2 NS@MIL-100(Fe) nanocomposites. The resulting sandwich-like TiO 2 NS@MIL-100(Fe) nanocomposites with enhanced adsorption ability and superior separation of photogenerated electron-hole pairs exhibited improved photoactivity toward degradation of methylene blue dye (MB) under visible light ( λ ≥ 420 nm). TiO 2 NS@MIL-100(Fe) nanocomposites offer an useful platform to integrate photocatalytic semiconductor and porous MOFs into hierarchical nanostructures with high surface areas and efficient electrons transfer for enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

As an important candidate for novel infrared semiconductor lasers, the optical properties of GaAsSb-based multiple quantum wells (MQWs) are crucial. The temperature- and excitation power-dependent photoluminescence (PL) spectra of the GaAs0.92Sb0.08/Al0.2Ga0.8As MQWs, which were grown by molecular beam epitaxy, were investigated and are detailed in this work. Two competitive peaks were observed from 40 K to 90 K. The peak located at the low-energy shoulder was confirmed to be localized states emission (LE) and the high-energy side peak was confirmed to be free-carrier emission by its temperature-dependent emission peak position. It is observed that the LE peak exhibited a blueshift with the increase of laser excitation power, which can be ascribed to the band filling effect of localized states. Our studies have great significance for application of GaAsSb-based MQWs in infrared semiconductor lasers. [ABSTRACT FROM AUTHOR]

The development of photocatalyst with hierarchical nanoarchitectures represents an attractive alternative that offers enormous increases in activity for solar photochemistry applications. However, the ability to obtain such hierarchical architectures on metal-organic frameworks (MOFs) based materials still remains a great challenge. Herein, we present a one-pot solvothermal process for the synthesis of a hierarchical MOF-based heterostructure composed of nanosheet-assembled MIL-88B(Fe) with the magnetic nanoparticles decoration. The unique nanosheet-constructed heterostructure can remarkably broaden the light absorption range to 660 nm and shorten the diffusion time for its open meso/macroporosity. This novel MOFs-based composite exhibited 3.46 (2.63) times as high visible-light-driven photocatalytic performance toward methylene blue (rhodamine B) dye discoloration as that of spindle MIL-88B(Fe). Meanwhile, the strategy for hierarchical heterostructure also imparted excellent magnetic separability at one stroke and favored the reusability and sustainability of the obtained composite as a photocatalyst for further applications. Our strategy provides a novel pathway in the rational design of advanced magnetic MOF-based materials for efficient photochemistry. [ABSTRACT FROM AUTHOR]

Hierarchical and hollow nanostructures have recently attracted considerable attention because of their fantastic architectures and tunable property for facile lithium ion insertion and good cycling stability. In this study, a one-pot and unusual carving protocol is demonstrated for engineering hollow structures with a porous shell. Hierarchical TiO2 hollow spheres with nanosheet-assembled shells (TiO2 NHS) were synthesized by the sequestration between the titanium source and 2,2′-bipyridine-5,5′-dicarboxylic acid, and kinetically controlled etching in trifluoroacetic acid medium. In addition, annealing such porous nanostructures presents the advantage of imparting carbon-doped functional performance to its counterpart under different atmospheres. Such highly porous structures endow very large specifics surface area of 404 m2 g−1 and 336 m2 g−1 for the as-prepared and calcination under nitrogen gas. C/TiO2 NHS has high capacity of 204 mA h g−1 at 1 C and a reversible capacity of 105 mA h g−1 at a high rate of 20 C, and exhibits good cycling stability and superior rate capability as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

A novel ferric chloride immobilized poly(4-vinylpyridine) (P4VP) catalyst was developed via a coordination chemistry-based approach. The pyridine moiety of poly(4-vinylpyridine) spheres functioned as the nitrogen donor to bind iron ions, as well as to decrease the amount of pyridine used in the catalytic reaction system. The monodispersed catalyst was well dispersed in the organic solvent during the catalytic procedure, taking advantage of its nanomorphology and uniform size. The catalytic activity of various monodispersed catalysts based different mass fractions of the divinylbenzene (DVB) was investigated, meanwhile the capacities of supported Fe(III) in the various catalysts were also discussed. The P4VPDVB 10% -Fe(III) catalyst exhibited high catalytic activity in the benzylic oxidation of benzylic methylenes and secondary benzylic alcohols. It was easily separated from the reaction system and reused several times without obvious degradation of catalytic activity. Moreover, leaching tests suggested that the as-synthesized P4VPDVB 10% -Fe(III) catalyst was a true heterogeneous catalyst without significant metal leaching. [ABSTRACT FROM AUTHOR]

The title reaction gives oxocarbenium precursors under mild conditions. [ABSTRACT FROM AUTHOR]

Core–shell C@poly(4-vinylpyridine) (C@P4VP) microspheres immobilized with small and uniform Au nanoparticles were designed and fabricated. Firstly, the C@P4VP support was obtained by coating a poly(4-vinylpyridine) shell on the carbon spheres through the hydrogen-bond interaction between –COOH of carbon spheres and pyridine of 4-vinylpyridine. Then Au nanoparticles were synthesized by in situ adsorption and reduction of HAuCl4 in the P4VP chains of the C@P4VP microspheres. Carbon spheres can serve as hard templates and prevent the polymeric P4VP shell from excessive deformation. The coordination between cross-linked networks of P4VP chains and the embedded Au nanoparticles effectively inhibit the aggregation and leaching of noble metal nanoparticles from the support. The resulting C@P4VP–Au microspheres showed excellent catalytic performance and high cyclic stability in the aqueous reduction of 4-nitrophenol by NaBH4. Moreover, optimal activities were observed for the P4VP shell with a low cross-linked degree and a reaction system with a low pH value. [ABSTRACT FROM AUTHOR]

• An electro- and photo- driven thermal phase change composite was designed. • Attractive interaction was regulated to promote crystalline-amorphous state transition. • CC facilitates electron and photon penetration, and ZIF reduces the convective heat loss. • ZIF-induced chain effect between PEG and CC enhances the mechanical properties. Metal organic frameworks contain abundant empty space for selectively absorbing phase change materials (PCM) molecules and sometimes chemically transformed. However, the strong attractive interaction between metal organic frameworks and PCM severely blocks sufficient crystalline-amorphous state transition of PCM. Herein, we proposed an attractive interaction engineering strategy on hierarchical zeolitic imidazolate frameworks (ZIF) based phase change materials (polyethylene glycol/carbon cloth@ZIF, PEG/CC@ZIF) for boosting crystalline-amorphous state transition behavior and electro-/photo- driven thermal performance. Carboxyl-modified CC scaffold regulates attractive interaction between ZIF and PEG, which enhances energy storage capacity of the phase change composite. Moreover, ZIF nanoflakes deposited on the surface of CC reduce the convective heat loss at the solid–gas interface, and CC scaffold facilitates electron transportation and photon penetration, thus significantly enhancing electro- and photo- driven thermal energy storage. Furthermore, ZIF-induced chain effect between PEG and CC enhances the mechanical properties of PEG/CC@ZIF. Notably, commercially available transition metal oxide photocatalyst can be uniformly sprayed on the surface of PEG/CC@ZIF through coordination chemical engineering for multi-functional phase change composite. [ABSTRACT FROM AUTHOR]

COREX is the primary process in the current smelting reduction method. The process has strict coal quality standards. Combustion processes of coal used in the COREX operating system were analyzed using a synchronous thermogravimetric analyzer combined with a mass spectrometer. The microcosmic structure and macerals were observed by an electronic scanning microscope. The qualitative and quantitative determinations of oxygen functional groups, such as phenolic hydroxyl, carboxyl, carbonyl, and methoxy groups were detected by the Fourier Transform Infrared spectrometer (FT-IR) and through chemical analysis methods. In addition, the evolution of the chemical structure and transformation mechanism of organic oxygen functional groups during COREX coal combustion have been thoroughly investigated. This study proposes a new coal-requirement index system and coal blending method, which will increase the expansion of coal selection and decrease the overall usage of coal during COREX. [ABSTRACT FROM AUTHOR]

Coal combustion catalysts of mesoporous perovskite-type LaCaMnO were prepared by sol-gel method. The resulting powder was characterized by scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction, dynamic light scattering and differential scanning calorimetry. After partially substituting La with Ca in LaMnO, Ca was found to occupy parts of La-site. As the substitution rate of Ca increased, the catalyst particle size distribution decreased and the pore size distribution of catalysts increased. Thermogravimetric measurements and combustion of coal in the presence of the LaCaMnO catalysis indicated that the presence of catalysts reduced the temperature for onset of coal combustion and increased the combustion rate. In fact, the addition of 1 % LaCaMnO to coal made the combustion point decrease by 41.5 K compared with coal alone. On the other hand, addition of 1 % LaCaMnO made the combustion rate increase by 22.2 % compared with combustion rate of organic coal. [ABSTRACT FROM AUTHOR]

Abstract: Polyaniline-modified Fe3O4/SiO2/TiO2 composite microspheres have been successfully synthesized by sol–gel reactions on Fe3O4 microspheres followed by the chemical oxidative polymerization of aniline. The synthesized multilayer-structured composites were characterized by TEM, XRD, TGA, UV–vis diffuse reflectance spectra and magnetometer. The photocatalytic activity was evaluated by the photodegradation of methylene blue under visible light. The effect of polyaniline (PANI) amounts on the photocatalytic activity was investigated. The photocatalytic activity results show that the Fe3O4/SiO2/TiO2 composites with about 2.4wt.%–4.1wt.% PANI could show higher photocatalytic efficiency than that of Fe3O4/SiO2/TiO2. Furthermore, the PANI-Fe3O4/SiO2/TiO2 photocatalyst could be easily recovered using a magnet. [Copyright &y& Elsevier]

Abstract: A simple three-axis model has been developed, which has been successfully applied to the analysis of the light transmittance in spatial incident angle and the simulation of modified formula of Malus’ law for Glan–Taylor prisms. Our results indicate that the fluctuations on the cosine squared curve are due to specific misalignments between the axis of the optical system, the optical axis of the prism and the mechanical axis (rotation axis) of prism, which results in the fact that different initial relative location of the to-be-measured-prism in the testing system corresponds to different shape of Malus’ law curve. Methods to get absolutely smooth curve are proposed. This analysis is available for other kinds of Glan-type prisms. [Copyright &y& Elsevier]

Nanosheets with large exposed surface and high chemical activity are of paramount significance for catalysis, gas sensing and energy storage. However, assembling them into large-area free-standing films and preventing aggregation of individual nanosheets remain a great challenge. Herein, an efficient strategy is proposed to assemble defect-rich TiO 2 (B) nanosheets into a 3D-scaffold structured free-standing film, which can preserve high chemical activity and prevent their aggregation. The inherent pores of Teflon lining are employed as load-bearing base to construct 3D scaffolds, and then, a rapid dissolution-recrystallization hydrothermal process is developed to fabricate defect-rich TiO 2 (B) nanosheets (~5 nm in thickness) on the 3D scaffolds. The numerous defects are crucial for boosting high rate performance within LIBs. The hierarchical 3D-scaffold structure endows the nanosheets-based electrode with outstanding cycling stability (96.1% retention after 6000 cycles at 6.7 A g−1), which hits a record high in terms of capacity retention for TiO 2 (B) nanosheets at high rate. The strategy for fabricating and assembling defect-rich TiO 2 (B) nanosheets paves the way for high performance LIBs. Image 1 • A template-free hydrothermal method is employed to construct 3D-scaffold structure. • Defect-rich TiO 2 (B) nanosheets-based free-standing film is successfully obtained. • The defect-rich nanosheets-based electrode exhibits outstanding cycling stability. [ABSTRACT FROM AUTHOR]

In this study, shape-stabilized composite phase change materials were fabricated by the impregnation method based on dodecanoic acid (DA) as energy storage material and graphene as a supporting matrix. The supporting material was prepared via in-situ filling with Na 2 CO 3 cores from solid sodium acetate and showed large specific surface area, high thermal stability, and large PCM loading ratio (81.1%), favorable pore characteristics and green and economical related to conventional graphene, carbon nanotubes and other 1D and/or 2D-carbon matrixes. The as-prepared composites were investigated by various characterization techniques to evaluate the performance of thermo-chemical and physicochemical properties. The resulted composite demonstrated an enhanced energy storage capacity of 157.6 kJ/kg, which was up to 101.4% higher than that of expected energy storage capacity with the reduced supercooling phenomenon. Due to supporting material that assisted the DA to nucleate heterogeneously. In addition, the composite revealed enhanced photo-thermal conversion about 78% and thermal conductivity up to 159.1% compared to that of pristine PCM with high reliability after 100 times thermal cycling, chemical compatibility and shape stability above the normal melting temperature of pristine DA. This signified that the composite is a promising material for practical applications like building heat preservation, air conditioning, and solar energy storage. Image 1 • Multifunctional composite PCMs were synthesized via an in-situ synthesis method. • The composite PCMs achieved up to 101.4% thermal energy storage capacity than expected energy storage capacity. • The composite exhibited a photo-thermal conversion capacity up to 78%. • The stability and thermal conductivity of composite PCMs were highly improved. [ABSTRACT FROM AUTHOR]

No abstract is available for this article. [ABSTRACT FROM AUTHOR]

The catalyst is recycled and reused in four additional cycles without loss of activity. [ABSTRACT FROM AUTHOR]