ChemSusChem

Make it snappy: Clicked 1,2,3-triazoles incorporated into anion-exchange membranes (AEMs) provide more sites to form efficient continuous hydrogen-bond networks for anion transport. Such molecular structures show a dramatic enhancement in anion conductivity compared to typical AEMs without triazole groups.

Not just sugar! Lewis-acidic Sn-MWW zeolites are obtained through postsynthesis functionalization of deboronated B-MWW with Sn. These materials are highly active, selective, and recyclable catalysts for the conversion of triose sugars to methyl lactate (in methanol) and lactic acid (in water). They also demonstrate good performance in the conversion of hexose sugars and sucrose to methyl lactate.

WO₃/W—wow! A self-biasing photoelectrochemical cell based on a Pt-catalyst-decorated crystalline silicon photovoltaic cell photocathode and WO₃/W photoanode that can be self-driven for overall water splitting under visible-light illumination is described.

Workin′ in a bromine: A palladium–polyoxometalate amphiphilic hybrid material serves as catalyst for oxidative brominations. The emulsion-based process avoids the use of toxic and corrosive bromination agents such as Br₂ or HBr, and uses molecular oxygen as oxidant. The only side product is water, which is also the reaction medium. The catalyst offers good recoverability and recyclability.

Dye-ing to degrade: The degradation mechanism of cyanoacrylic acid-based organic sensitizers in dye-sensitized solar cells (DSSCs) has been studied. With the synergy of water and UV light, the sensitizer desorbs from the TiO₂ surface and the cyanoacrylic acid unit of sensitizer is converted into an aldehyde group. It is also observed that the oxygen atom of the aldehyde comes from the solvent water in DSSCs.

Membrane fame! A membrane with short side chains is proposed for vanadium flow batteries for the first time. This membrane (Aquivion-E87-12S) displays a much lower degree of hydrophobic–hydrophilic separation and exhibits superior coulombic efficiency than Nafion along with a remarkable capacity retention.

Down to the wire: Three-dimensional interconnected Si-based nanowires are produced through the combination of thermal decomposition of SiO and a metal-catalyzed nanowire growth process. This low-cost and scalable approach provides a promising candidate for high-capacity anodes in lithium-ion batteries.

Wax on, wax off: Bifunctional cobalt-based catalysts on zeolite supports are applied for the valorization of biosyngas through Fischer-Tropsch chemistry. By using these catalysts, waxes can be hydrocracked to shorter-chain hydrocarbons, increasing the selectivity towards the C₅–C₁₁ (gasoline) fraction. The zeolite topology and the amount and strength of acid sites are key parameters to maximize the performance of these bifunctional catalysts, steering Fischer-Tropsch product selectivity towards liquid hydrocarbons.

A river runs through: Sediment microbial fuel cells are a new technology used to harness the natural redox gradients in sediments to produce usable energy. Microbial catalysis of oxygen reduction is often used to enhance the recovery of energy by sediment microbial fuel cells. It is demonstrated that microscale gradients of pH, oxygen, and hydrogen peroxide resulting from oxygen reduction negatively affects the colonization of micro-organisms on cathode surfaces that could be used in sediment microbial fuel cells.

Facing the pyramids by etching forward: Concave palladium polyhedra have been successfully prepared by selectively etching the {100} facets in situ by I⁻ ions. Due to the presence of a high density of atomic steps and surface relaxation, the concave palladium polyhedra exhibit an enhanced electrocatalytic activity towards ethanol oxidation.

Plasma increases activity: A one-step synthesis of Pt–C nanowire composites using a plasma co-deposition method is reported. Electrodes with a very low Pt loading can be obtained. Pt particles with sizes ranging from 1 to 2 nm are decorating the columnar carbon nanostructures because of strong interactions. The composite microstructure is responsible for a very high metal utilization rate as exemplified by reactions occurring in fuel cell electrodes.

It’s a cover up! A new organic dye self-assembled on ZnO surface through carboxylate bonding has positive effects on the photovoltaic performance of inverted polymer solar cells (PSCs). This dye is based on a D–π–A system and can mediate forward charge transfers, reduce back charge recombination, passivate ZnO surface defects, and give good energy level alignments leading to largely enhanced efficiency and stability in inverted PSCs.

Feed the pore: A highly mesoporous melamine–formaldehyde resin is synthesized through a simple, one-step polycondensation reaction by using inexpensive and abundant common industrial chemicals. The material is demonstrated to have a high surface area and a well-defined pore structure. Its high density of CO₂ binding pockets with low CO₂ binding energy facilitates rapid and reversible CO₂ sorption.

Benign building blocks: Stereochemically pure diisocyanates were prepared on a multigram scale from succinic anhydride and isosorbide or isomannide. Characterization of polyurethanes that were produced from these diisocyanates revealed low polydispersity, high thermal stability, and stereochemistry-dependent morphology. If biobased succinic anhydride is used, then no stoichiometric petroleum-derived reagents are required in the synthesis of these materials.

Mild-mannered manipulation: A catalytic method for the conversion of carbohydrate biomass to γ-valerolactone in acidic aqueous media has been developed. The water-soluble iridium complexes were observed to be extremely catalytically active for providing γ-valerolactone in high yields with high TONs. The homogeneous catalysts can also be recycled and reused by applying a simple phase separation process.

Our best results jet: C₁₀ and C₁₁ branched alkanes, with low freezing points, are synthesized through the aldol condensation of furfural and methyl isobutyl ketone from lingocellulose, which is then followed by hydrodeoxygenation. These jet-fuel-range alkanes are obtained in high overall yields (≈90 %) under solvent-free conditions.

Polymer power: A polyethylene oxide-based electrolyte was prepared with the addition of silane-treated Al₂O₃ ceramic filler. The new ceramic additive leads to an enhancement of the ionic conductivity, thermal properties, and lithium transference number of the polymer electrolyte. The electrolyte can be efficiently used in lithium cells with a LiFePO₄ cathode, operating within 60–90 °C with a high capacity and a long cycle life.

Formic acid cracker: A mini plant that allows for continuous formic acid decomposition to hydrogen and carbon dioxide under ambient conditions is presented. By using an in situ-formed ruthenium catalyst, unprecedented turnover numbers over 1 000 000 are achieved. The active catalyst is formed in situ from commercially available [RuCl₂(benzene)]₂ and 1,2-bisdiphenylphosphinoethane.

Chain reaction: The esterification of glycerol carbonate with carboxylic acids to produce glycerol carbonate esters, which are valuable biomass-derivative compounds, has been investigated. A Nafion–silica nanocomposite is shown to be an excellent catalyst, and after fitting the experimental data to a kinetic model, the kinetic parameters were determined and compared for reactions involving different carboxylic acids.

RuC ees′ transfer: Transfer hydrogenation using alcohols as hydrogen donors and supported ruthenium catalysts results in the selective conversion of hydroxymethylfurfural to dimethylfuran (>80 % yield). During transfer hydrogenation, the hydrogen produced from alcohols is utilized in the hydrogenation of hydroxymethylfurfural.

Battery watch: UV/Vis spectrophotometry is demonstrated as a powerful analytical method for the in situ study of polysulfides. Through the interactions that occur between different chain-length polysulfide molecules and the UV/Vis radiation, quantitative and qualitative determination of the polysulfides formed during Li–S battery operation can be achieved.

Snuggling of bucky and methane: What are the preferred adsorption sites of methane on small aggregates of C₆₀? How many methane molecules adsorb in groove sites? How many in dimple sites? We provide answers for aggregates containing up to four C₆₀ molecules. For example, this figure shows that seven CH₄ fit into the groove of the dimer, in excellent agreement with experiment. Calculated adsorption energies of 118–281 meV are in the optimal range for high-density storage of natural gas.

Sucked in! Polyethyleneimine (PEI)-functionalized polymeric hollow-fiber sorbents for post-combustion carbon dioxide capture are described. Different molecular weight PEIs are studied as functional groups on polyamide imide (PAI) hollow fibers. For equivalent PEI concentrations, PAI functionalized with lower molecular weight PEI exhibit higher CO₂ capacities (see picture).

Fuel for thought: The dedicated production of 1,3-butadiene from bioethanol is expected to be an effective solution to its current substantial price increase. The Lebedev process for ethanol-to-butadiene conversion is reviewed in detail. The Review also extends to other commodity chemicals that are produced from ethanol and are involved as intermediates or byproducts in the bio-based butadiene production process.

Rough and ready: A platform technology for the hydrophobization of natural fibers in water through amphiphilic block copolymer micelle adsorption onto fibers and subsequent heating. The natural roughening of the fibers upon drying facilitates hydrophobization, and heating reveals the hydrophobic core, which allows further hydrophobizing of the surface. Heat treatment tunes the effect of changes to the advancing water contact angles of 120° to 150°.

Say it ain′t SO₂! The ionic liquid [Et₂NEMim][Tetz] is synthesized and demonstrated to have an extremely high absorption capacity and rapid absorption/desorption rates for the capture of SO₂. [Et₂NEMim][Tetz] can be regenerated and reused, making it a very attractive ionic liquid for practical SO₂ capture applications.

CuInS a phase: An amorphous Cu–In–S nanoparticle-based route to form dense CuInSe₂ absorber layers for thin-film solar cells, in which the precursor nanoparticles are prepared within one minute of reaction without external heating, is demonstrated. A power conversion efficiency as high as 7.94 % is achieved by using this method.

Complex fertilizers: The combination of computational chemistry and traditional analysis allows the explanation of unexpected trends in the intensity and fine structure of the peaks obtained through ³¹P NMR spectroscopy for phosphate-based fertilizers. A sulfate–calcium-humate complex is predicted and confirmed, which has not previously been reported.

In a spin: The major discharge product formed in the lithium–oxygen cell, lithium peroxide, exhibits a magnetic moment. Density functional calculations predict that “superoxide-like” surface oxygen groups with unpaired electrons exist on nanoparticle surfaces, consistent with magnetic measurements of discharged lithium peroxide products. The “superoxide-like” surface oxygen groups with spin can play a role in the reversible formation and decomposition of lithium peroxide as well as electrolyte molecules.

Two-faced: Hausmannite Mn₃O₄ nanoparticles with (101) facets were prepared through oxygen-mediated growth. The Mn₃O₄ octahedral nanoparticles exhibited high mass-specific capacitance and cycle ability for supercapacitor reactions. The charge-storage mechanisms of the nanoparticles during electrochemical redox reactions were further studied by using in situ synchrotron-based methods.

Acid/Metal Balance: Bifunctional catalysts containing ruthenium and polyoxometalates as active species with a metal-organic framework as support and encapsulation matrix, respectively, are synthesized. Excellent yields in sorbitol are obtained in the conversion of cellobiose and ball-milled cellulose. The evaluation of the balance between the hydrogenation and hydrolysis functions of these bifucntional catalysts reveals that by carefully balancing the ratio of acid site density and the number of metal surface atoms a maximum conversion can be achieved.

Cat-Al-ytically coated: The preparation of a solid acid foam based on zirconium phosphate (ZrPO) coating on aluminum foam is described. The catalytic properties are evaluated in the dehydration of glucose to 5-hydroxymethylfurfural in a biphasic rotating foam reactor (see picture). The silylation procedure leads to a higher selectivity, and a more intensive contact of the foam with aqueous and organic phases leads to an increase of selectivity and stability.

Left out to dry: Aqueous-phase reforming (APR) of biocarbohydrates is conducted for the first time in a catalytically stable washcoated microchannel in which multiphase hydrogen removal enhances the hydrogen efficiency. The microchannel presents higher conversion of ethylene glycol and higher selectivity to hydrogen than a fixed-bed reactor. The use of microreactor technology for APR allows for a great reduction in the reformer size, which is promising for distributed hydrogen production.