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Organic solar cell (OSC) development continues to demonstrate impressive device efficiency improvements. However, the materials synthetic simplicity essential to industrialization remains seriously lacking attention, imparting inferior performance records in low‐cost devices. Hence, low bandgap and completely non‐fused electron acceptors (CNFEAs) having simple molecular structures are investigated herein. In contrast to typically explored fused‐ring acceptors with smaller backbone conformational variations, minimizing the interface recombination sites through a greater extent of localized domains is identified as more critical in CNFEAs, leading to remarkable fill factors (FFs) approaching 75%, among the highest currently realized for low‐cost systems. However, this comes with diminishing charge generation efficiency. The general ternary blend optimization strategy modifying the morphology of host components is limited in preserving such remarkably high FFs. To suppress the trade‐off while keeping notable FFs, a new perspective of constructing functionally bridged components based on optical, electronic, and thermodynamic properties is introduced here. Specifically, charge generation is unrestrained from the host acceptor localized domains through the introduction of a "bridge" component while also taking advantage of the configuration to channel polarons toward the efficient transport moieties of the host components. Accordingly, this work incubates understanding‐guided optimizations toward the advancement of more practical devices. [ABSTRACT FROM AUTHOR]

An electro-Fenton-like reaction process relying on peroxymonosulfate activation can stably degrade chloramphenicol (CAP) within 16 min, where the kinetic rate constant can be as high as 0.089 min−1 and the energy consumption value can be as low as 25.1 kWh•m^−3. Evidence indicated that the use of a Na2SO4 solution as the electrolyte can enhance CAP degradation due to rapid electron transfer properties. The generated electrons and active free radicals are responsible for CAP degradation, and the electrons can be transferred from the highest occupied molecular orbital of CAP to the lowest unoccupied molecular orbital of peroxymonosulfate via the PbO2 electrode. Density functional theory calculations based on Fukui index analysis elucidated the key attack sites in CAP; moreover, reaction-free energy calculations shed light on potential CAP degradation pathways. Not only does this study afford an insight into the activation of peroxymonosulfate for organic pollutant degradation but also provides an innovative technology with potential applications in wastewater purification. [ABSTRACT FROM AUTHOR]

Although Fenton-like reactions have been extensively used to treat various organic contaminants in wastewaters (oily wastewaters, landfill leachate, denitrification with Fenton oxidized non-degradable large molecular organic pollutants, and removal of phosphorus, etc.), the difficulty in catalyst recovery and the instability of catalytic activity limit their practical application. Herein, iron atoms were inserted in a metal-organic framework (FeNC) with dual reaction sites as highly reactive and stable electro-Fenton-like catalysts for the catalytic oxidation of organic pollutants via the electro-Fenton-like activation reaction of peroxymonosulfate (PMS) with fractional leaching of metal ions. Experiments and density functional theory (DFT) calculations indicate that FeNC with FeN4 and Fe–Fe active sites can rapidly deliver electrons for PMS dissociation. Further, an electrolysis reactor was constructed for the on-site generation of reactive oxygen species, which can stably and continuously purify various organic wastewaters. The combined use of an electrolysis reactor and magnetic catalyst in the current study provides a direction for the long-term remediation of organic pollutants on an industrial scale. [ABSTRACT FROM AUTHOR]

Moisture removal and water recovery from the air are vital for regulating indoor humidity and mitigating water scarcity. Most atmospheric water harvesters (AWH) focus primarily on increasing the moisture capture rate, but for it to be economical and sustainable, it is essential to consider the energy required to recover and harvest the captured water. Here, a mechanically flexible, biphilic sorption‐based AWH made of green, environmentally friendly material is presented. It consists of a hygroscopic chitosan polymer embedded within a flexible, hydrophobic silica xerogel that can harvest 86.3 g water/g chitosan at 97% relative humidity and 25°C reaching saturation after 30 days (i.e. 2.88 g water/g chitosan/day). Roughly 88% of the sorbed moisture was recovered by mechanical squeezing (ca. 0.020 MPa) within 150 s. Repeated water harvesting experiments and uniaxial compression tests demonstrate that chitosan‐silica xerogel is durable for long‐term operations, providing a fast, reliable, and sustainable moisture removal and water harvesting tool. [ABSTRACT FROM AUTHOR]

Rapid population growth and widespread industrialization are the main contributing factors to the increasing contamination of the world's diminishing freshwater resources. This work investigates Fe/TiO2 as an efficient and sustainable photocatalyst for treating organic micropollutants in water. The photocatalysts prepared by these mechanochemical methods used a high-energy ball milling technique to manipulate Fe/TiO2's structural, optical, and catalytic properties for the photo-oxidation of 2,4-Dichlorophenol (2,4-DCP). Doping with iron effectively reduced the band gap of rutile TiO2 from 3 to 2.22 eV. By reducing the ball/powder ratio from 34 to 7, the removal efficiency of 2,4-DCP increased from 65.2 to 84.7%. Measuring the TOC indicated 63.5 and 49.4% mineralization by Fe/TiO2-7 and rutile TiO2, respectively, after 24 h. The energy yields for the Fe/TiO2 and rutile TiO2 were 0.13 and 0.06 g 2,4-DCP/kW h, respectively. [ABSTRACT FROM AUTHOR]

This work describes a versatile electrospinning equipment with rapid, independent, and precise x–y–z movements for large-area depositions of electrospun fibers, direct writing or assembly of fibers into sub-millimeter and micron-sized patterns, and printing of 3D micro- and nanostructures. Its versatility is demonstrated thought the preparation of multilayered functional nanofibers for wound healing, nanofiber mesh for particle filtration, high-aspect ratio printed lines, and freestanding aligned nanofibers. [ABSTRACT FROM AUTHOR]

In this study, we investigated the antibacterial properties of nanostructured Ag@SiO2–penicillin synthesized from triangular silver nanoplates (Ag NPs) against methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) bacteria. The Ag@SiO2–penicillin nanoparticles contained approximately 33.2 wt% Ag as determined by ICP-OES. Grafting of about 2.8 wt% penicillin on Ag@SiO2 remarkably enhanced the bactericidal properties against MSSA and MRSA bacteria and showed no cell-death inducing effects towards the A431 cell line. [ABSTRACT FROM AUTHOR]

Polystyrene (PS)‐dioctyl phthalate (DOP) films were prepared by spin coating solutions of a mixture of PS and DOP on Si wafers and characterized by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS). ToF‐SIMS depth profile results showed that DOP mainly segregated to the top 10 nm of the surface of the PS‐DOP film as well as to the interface between the film and the substrate. The normalized intensities of the ions corresponding to DOP on the surface increased as the annealing temperature increased and reached a maximum at the annealing temperature of 60°C, and then decreased as the annealing temperature increased. XPS results indicate that the maximum amount of DOP segregated to the top surface of the PS‐DOP film can reach to 39 wt% at the annealing temperature of 60°C. In addition, DOP evaporated at 25°C under ultra‐high vacuum conditions; hence, ToF‐SIMS and XPS analyses need to be carried out at low temperatures (e.g., −40°C). [ABSTRACT FROM AUTHOR]

Defects were created on the surface of highly oriented pyrolytic graphite (HOPG) by sputtering with an Ar+ ion beam, then characterized using X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) at 500°C. In the XPS C1s spectrum of the sputtered HOPG, a sp3 carbon peak appeared at 285.3 eV, representing surface defects. In addition, 2 sets of peaks, the Cx− and CxH− ion series (where x = 1, 2, 3...), were identified in the ToF‐SIMS negative ion spectrum. In the positive ion spectrum, a series of CxH2+• ions indicating defects was observed. Annealing of the sputtered samples under Ar was conducted at different temperatures. The XPS and ToF‐SIMS spectra of the sputtered HOPG after 800°C annealing were observed to be similar to the spectra of the fresh HOPG. The sp3 carbon peak had disappeared from the C1s spectrum, and the normalized intensities of the CxH− and CxH2+• ions had decreased. These results indicate that defects created by sputtering on the surface of HOPG can be repaired by high‐temperature annealing. [ABSTRACT FROM AUTHOR]

Graphite oxide powder was obtained using the modified Hummers’ method and characterized using X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The XPS results indicated that the epoxy groups were the main functional groups on the graphite oxide powder surface. The graphite oxide powder was then reacted with SO2 and NH3 gases, respectively, at 25 °C. The XPS and ToF-SIMS analyses of the surface of the reacted graphite oxide powder showed that the reactions mainly occurred in the epoxy groups. Bisulfate and amine groups were formed on the surface of the graphite oxide powder after the reactions between the graphite oxide powder and SO2 and NH3 gases. This work demonstrates a new method of removing SO2 and NH3 gases using graphite oxide powder. [ABSTRACT FROM AUTHOR]

We studied the time‐of‐flight secondary ion mass spectrometry fragmentation mechanisms of polystyrenes—phenyl‐fluorinated polystyrene (5FPS), phenyl‐deuterated polystyrene (5DPS), and hydrogenated polystyrene (PS). From the positive ion spectra of 5FPS, we identified some characteristic molecular ion structures with isomeric geometries such as benzylic, benzocyclobutene, benzocyclopentene, cyclopentane, and tropylium systems. These structures were evaluated by the B3LYP‐D/jun‐cc‐pVDZ computation method. The intensities of the C7H2F5+ (m/z = 181), CyPent‐C9H3F4+ (m/z = 187), CyPent‐C9H4F5+ (m/z = 207), and CyPent‐C9H2F5+ (m/z = 205) ions were enhanced by resonance stabilization. The positive fluorinated ions from 5FPS tended to rearrange and produce fewer fluorine‐containing molecular ions through the loss of F (m/z = 19), CF (m/z = 31), and CF2 (m/z = 50) ion fragments. Consequently, the fluorine‐containing polycyclic aromatic ions had much lower intensities than their hydrocarbon counterparts. We propose the fragmentation mechanisms for the formation of C5H5+, C6H5+, and C7H7+ ion fragments, substantiated with detailed analyses of the negative ion spectra. These ions were created through elimination of a pentafluoro‐phenyl anion (C6F5−) and H+, followed by a 1‐electron‐transfer process and then cyclization of the newly generated polyene with carbon‐carbon bond formation. The pendant groups with elements of different electronegativities exerted strong influences on the intensities and fragmentation processes of their corresponding ions. [ABSTRACT FROM AUTHOR]

Substrate modification by an ultrathin ZnO layer followed by surface activation promotes homogeneous surface nucleation and the growth of a low-defect ZIF-8 tubular membrane that exhibits superb gas permeation and permselectivity. [ABSTRACT FROM AUTHOR]

Pd membranes of excellent stability and flux were prepared with multi-legged anchors by electroless plating of Pd on a porous support modified by a zeolite barrier layer containing Pd seeds; these membranes provide stable phenol production by direct hydroxylation of benzene. [ABSTRACT FROM AUTHOR]