Metal-organic frameworks (MOFs) are a new class of crystalline porous materials, having wide pores which provide extremely high specific surface areas, larger than those typically observed in more common porous materials like zeolites or activated carbons. This peculiar property combined with the frequent presence of open-metal sites, makes them very promising for a broad range of applications, spacing from gas storage or separation, drug delivery, toxic air removal, chemical detectors, etc. However, the industrialization of MOFs is still facing difficulties because of their low stability to water or even air moisture, a substance difficult to avoid in applications like those mentioned. Another issue concerning MOF industrialization consists in the low bulk density of the micrometric powder grains, which typically constitute such materials. Unfortunately, their low mechanical stability seems to make difficult even to enhance the packaging by simple mechanical compaction. In this review, we will particularly focus on the current state of art involving the MOF HKUST-1, especially on the degradation process involved when this MOF interacts with water molecules. Furthermore, we will show the connection between water and mechanical stability, bringing to attention of a study where solid tablets of HKUST-1 powder have been realized without any loss of crystallinity or porosity because of an accurate study on the effects of different degree of hydration during the tableting phases. In addition, in order to highlight the causes of damages induced in the framework upon interaction with water, a comparison with other two copper carboxylate MOFs will be shown, namely STAM-1 and STAM-17-OEt, which differ from HKUST-1 uniquely for the organic ligands.

Chemical functionalization of graphene greatly expands its potential in electronic, photovoltaics and bio-logical applications. The band gap tunability of graphene achieved during the process of its hydrogenation and dehydrogenation can open its potential as an acceptor material in organic photovoltaic (OPV) solar cells. In this paper, we report a rapid and extensive hydrogenation of single layer graphene (SLG) by Birch reduction followed by its oxidation back to the conducting SLG. Dehydrogenation of hydrogenated SLG using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as an oxidising agent was performed successfully. Raman, FT-IR and UV-Vis spectra provides supporting evidence for a successful dehydrogenation reaction. A control experiment without DDQ as an oxidant confirms its active role as an oxidising agent. Magnetic moment study reveals a reversibility of ferromagnetic hydrogenated SLG to a paramagnetic dehyrdrogenated SLG. Finally, the sheet resistance measurement of pristine, hydrogenated and dehydrogenated SLG shows almost complete reversal of the electrical conductivity.

Advances in the synthesis of low bandgap (E _g < 1.5 eV) conjugated polymers has produced organic materials capable of absorbing near-infrared (NIR) light (800—2500 nm), with these materials first applied to photodiode NIR detectors in 2007 as an alternative to more traditional inorganic devices. Although the development of organic NIR photodetectors has continued to advance, their ability to effectively detect wavelengths in the low-energy portion of the NIR spectrum is still limited. Efforts to date concerning the production of photo-diode-based devices capable of detecting light beyond 1000 nm are reviewed.

Aqueous pollution from industrial dyes and antibiotics has brought up much threat to our daily healthy life. In the present work, hydrogenated black TiO ₂ nanoparticles (H-TiO ₂) are synthetized, their properties are studied, and their potentials in removing dyes (methylene blue, M.B.) and antibiotics such as tetracycline hydrochloride (TC) and ciprofloxacin (CIP) are explored with the support of statistical optimization. The operational controlled parameters such as catalyst amount (g L ⁻¹), pH and irradiation time (min) were optimized using Design of Experiment (DOE) L9 Taguchi Orthogonal Array. From Analysis of Variance (ANOVA) results, it can be seen that irradiation time is the most influencing parameter for % MB color removal, % Degradation of TC and CIP, over catalyst amount and pH. The optimal parameters found here are 0.50 g L ⁻¹ of hydrogenated H-TiO ₂-750 as catalyst, pH 4 for MB, pH 11 for TC and pH 2 for CIP, respectively. In addition, an irradiation time of 30 min shows a maximum MB color removal of 95.05%, TC 94.8% and CIP 92.25%. Irradiation time is found to be the most influencing parameter (71.08% for MB, 55.33% for TC and 52.77% for CIP) followed by catalyst amount (28.82% for MB, 44.19% for TC and 41.5% for CIP) and in the end pH (0.09% for MB, 0.47% for TC and 5.72% for CIP). With the use of hydrogenated H-TiO ₂-750, the dye and antibiotics degradation reaches almost 40% more than using TiO ₂ pristine anatase.

Nanomaterials are attracting renewed interest due to their novel properties, which are not seen in their conventional micro state counterparts. They are used in advanced applications in the fields of catalysis, medicine, electronics, optics and membranes. Electrospinning is one of the simplest and cheapest methods to make nano-porous polymer membranes, and these offer a large surface area-to-volume ratio, high porosity and small pore size. These electrospun nonwoven mats could be employed in myriad applications ranging from filtration, sensors, electrode materials, drug delivery, cosmetics, and tissue scaffolding. This technique can introduce novel functional characteristics, and hence by changing the basic experimental set up, solvent, solution and polymer characteristics can alter the composition, morphology, and porosity of the processed material. The unique structural and functional characteristics inherited at submicron to nanoscale dimensions via electrospinning makes it an attractive technique for advanced industrial applications.

Fullerenes have attracted much attention because of their unique electronic structure and spherical cage shape. Specially, fullerenes have been widely used as guest in supramolecular chemistry due to their spherical structures. Recently, the supramolecular complexes of fullerenes and several types of carbon nanorings have been constructed and investigated. The complex of fullerene in carbon nanoring is like a Saturn, and this unique kind of supramolecular complexes will have potential applications in chemical, material and physical fields. In this review, various complexes of fullerene in carbon nanoring and their special properties are described. We hope to expand the application of these supramolecular complexes in various fields.

Dried foam films (DFF) of graphene oxide (GO) has been prepared by dipping a titanium mesh in the solution of GO, and then it was reduced by electrochemical method. Next, the as-prepared water-containing reduced grapheme oxide (rGO) DFF film works as electrode for electrocpolymerization of aniline onto its surface for preparing a polyaniline/graphene monolith while the titanium mesh acts as the electron collector. The as-obtained composite film is binder-free and has highly surface area, conductivity, and can be used for supercapacitor electrode. Then network of plenty polyaniline nanoparticles formed on the surface of rGO film by electrochemical polymerization, which works as the material for pseudocapacitance. When the film is used as a supercapacitor electrode, the maximum specific capacitance is as high as 633.4 F g ⁻¹ and the specific capacitance retains 75% of the initial after constant charge discharge 5000 cycles at current density of 10 A g ⁻¹, indicating that the nanocomposite is a suitable active material for supercapacitors.

The properties of surfaces are crucial for many processes in a variety of areas in biology, industry, and daily life. Surprisingly, even though surface phenomena have been studied for more than 200 years by some of the greatest physicists, mathematicians, and engineers, there are still quite a few enigmas to be solved. This paper presents some fundamental enigmas related to the surface tensions of liquids and solids that were either partially solved or yet mostly unsolved.

Carbon dots are small carbon nanoparticles with effective surface passivation by mostly organic species. For such a simple and well-defined nanoscale structure, the classical and most reliable synthesis is the use of pre-existing small carbon nanoparticles for surface chemical functionalization with organic molecules. However, a more popular synthetic approach in the literature has been the “one-pot” carbonization of organic precursors, which with appropriate processing conditions could in principle create local structures in the resulting dot-like entities that may be comparable to the structural configuration in carbon dots, though the carbonization can also easily produce colored organic materials crosslinked into the sample structures. An extreme example was the thermal processing of the specific organic precursor mixtures including only citric acid with formamide or urea to yield samples of red/near-IR absorption and emission features, which prompted the claims of “red/near-IR carbon dots”. In reality, these spectral features have nothing to do with nanoscale carbon, let alone carbon dots, but simply associated with molecular dyes/chromophores produced in chemical reactions of the specific precursor mixtures under the thermal processing conditions intended for carbonization. In this work, the isolation and identification of the responsible molecular dyes/chromophores were pursued. The results present further evidence for the conclusion that the red/near-IR absorption and emission features have nothing to do with carbon dots.

President Kennedy’s dream of obtaining fresh water from seawater seemed has been realized as a great scientific achievement. As Norihito Tambo predicted, seawater reverse osmosis desalination (SWRO) has become a major technology in Middle Eastern countries. SWRO requires less energy compared with the distillation method. Even Middle Eastern countries, where the distillation method is still a major technology, have started to adopt the RO method in new desalination plants in accordance with government policy and following the trend of developing larger (half mega-ton per day and larger) so-called Mega-SWRO plants. With these trends in the global market, the requirements of sustainable SWRO desalination as green desalination for the 21 ^st century are as follows: (1) conservation of energy resources: renewable energy, (2) innovation of desalination technologies: new advanced membrane and membrane systems, (3) reduction of marine pollution: green desalination. The government-supported Mega-ton water system project has been conducted to solve issues related to (2) and (3). The combination of a low pressure SWRO membrane and a low-pressure, two-stage, and high-recovery SWRO system, also referred to as a SWRO-PRO hybrid system, it has enabled 20% energy reduction and 30% energy saving in total. Likewise, low environmental impact as green desalination has established a reliable operation using less chemical and chemical cleaning. In terms of low-cost renewable energy, in particular, solar energy is now available to solve issues related to renewable energy. By combining these sophisticated technologies, desalinated water has become affordable at $ 0.50/m ³ or less (as low as $ 0.28/m ³). SWCC has announced their future plans for SWRO. The main topic is directed to brine mining to obtain precious materials from the brine of SWRO. This plan will be connected to water and green hydrogen for a sustainable future.

The Meyer-Schuster rearrangement reaction has been known for almost a hundred years. It has been used to prepare unsaturated aldehydes, ketones, and even esters from propargyl alcohols. Thirty years ago, the same reaction was found to produce also α-halogenated aldehydes and ketones under suitable conditions. In the last thirty years, several methods have been developed utilizing the Meyer-Schuster rearrangement in the synthesis of halogenated building blocks for use in synthetic chemistry. In this perspective, we describe the progress in the field.

Two novel fluorenyl-porphyrins 2Flu-TPP and 4Flu-TPP serving as charge trapping elements are designed and synthesized through BF ₃.Et ₂O catalyzed Friedel-Crafts reaction. With steric hindrance building blocks of fluorene units, 2Flu-TPP and 4Flu-TPP present highly nonplanar 3-dimensional structure, which could effectively inhibit molecular packing and intermolecular arrangement of porphyrins. As charge trapping elements, porphyrin groups provide the hole trapping sites, while fluorene units act as a hole blocking group to reduce the formation of leakage current paths. The pentacene-based organic field effect transistor memory devices based on 2Flu-TPP and 4Flu-TPP show memory windows of 48.93 and 49.20 V, respectively. The 2Flu-TPP device shows reliable endurance property with a large ON/OFF current ratio (1.1×10 ⁷) and good charge retention time (2.41×10 ⁵ after 2×10 ³ s). This study suggests that porphyrin based steric hindrance small molecular elements have great promise for high-performance organic field effect transistor memory.

The dissociative chemisorption and energetically driven migration of atomic hydrogen on heterogenous electrocatalysts, i.e., hydrogen spillovers, which occur during electrochemical turnovers, have been intensively investigated recently on high-performance electrocatalysts for hydrogen evolution reaction. The elucidation of the hydrogen spillover not only reshapes the mechanistic understanding of the catalytic landscape but also aids in formulating efficient reaction pathways for catalyst designs. This perspective hence concisely summarizes the status of research on the hydrogen spillover effect in recent years, as well as the experimental methods to characterize the hydrogen spillover process and presents a prospect for future research direction.

As one of the key  components of perovskite solar cells (PSCs), hole transport materials (HTMs)  effectively improve the performance and stability of the devices and greatly promote the development of PSCs. At present, due to the advantages of flexible structure design, simple synthesis, low-cost and abundant raw materials, organic  small molecule HTMs have been studied extensively by researchers. Among them, small molecule HTMs  with donor–acceptor (D –A) type structures for PSCs have received great attention in the last few years because of their high hole mobility due to strong dipolar intermolecular interactions,  minimizing ohmic losses of the contact, good stability, and high solubility. In this review, we mainly introduce some representative  D−A−D-type  small molecule HTMs, summarize and comment on their properties, and discuss the relationship between molecular structure and performance parameters of devices. Finally, based on the current research, the future design of new efficient HTMs is prospected.

Spiro[fluorene-9,9′-xanthene] has received great attention due to its unique structure and possesses wide applications in the field of material chemistry. Herein, we highlighted low-cost, stable and high-performance spiro[fluorene-9,9′-xanthene] derivatives for organic electronics.

In this paper, we developed and validated a simple and accurate thin layer chromatography method for the analysis of the chemical components in the plants of genus Lindera (the Lauraceae family). High performance liquid chromatography method was used to verify the results of thin layer chromatography analysis.

Chemical crosslinking technology was rapidly developed and utilized to prepare structurally fixed, stabilized and functionalized polymer nanoassemblies and nanoarchitectures by covalently reinforcing the interactions between the polymer chains. This perspective reviewed recent advances on the crosslinked polymer nanoassemblies and their applications, mainly in drug delivery. Moreover, possible future research outlooks in the field of Shell-crosslinked polymer nanoassemblies were also stated and discussed.

Thiophenols, a family of important industrial chemicals, is highly toxic for aquatic organisms and human beings. Developing new chemical sensors with the merit of fast, low cost, portable, selective and sensitive, as well as visualizable signal output for efficient detection of thiophenols, is highly desirable. This spotlight article reviewed and discussed the current trend and statement of thiophenols-specific fluorescent probes. Moreover, the future outlook in this field was also stated.