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Organic piezoelectric nanogenerators (PENGs) are attractive in harvesting mechanical energy for various self‐powering systems. However, their practical applications are severely restricted by their low output open circuit voltage. To address this issue, herein, we prepared two two‐dimensional (2D) covalent organic frameworks (COFs, CityU‐13 and CityU‐14), functionalized with fluorinated alkyl chains for PENGs. The piezoelectricity of both COFs was evidenced by switchable polarization, characteristic butterfly amplitude loops, phase hysteresis loops, conspicuous surface potentials and high piezoelectric coefficient value (d33). The PENGs fabricated with COFs displayed highest output open circuit voltages (60 V for CityU‐13 and 50 V for CityU‐14) and delivered satisfactory short circuit current with an excellent stability of over 600 seconds. The superior open circuit voltages of CityU‐13 and CityU‐14 rank in top 1 and 2 among all reported organic materials‐based PENGs. [ABSTRACT FROM AUTHOR]

The advent of utilizing nitrate (NO3−) for electrochemical co‐reduction with carbon dioxide (CO2) to effectively synthesize high‐value‐added organic nitrogen compounds has captured the attention of the environmental and energy fields. C─N coupling is a key step during the electrochemical co‐reduction process. An effective strategy to improve the efficiency of synthesis is to explore the optimal reaction pathway and coupling active species. Herein, a p‐type semiconductor nanosphere (Ti‐DHTP) is presented for electrochemical co‐reduction to synthesize urea by combining CO2 and NO3−. At a low voltage of −0.6 V versus RHE, the electrochemical synthesis of urea exhibits 95.5% C‐selectivity and 21.75% Faraday efficiency. Comparative experiments, in situ experiments, and theoretical simulations confirm that a new coupling pathway for the synthesis of urea from *NH2 and *OCO intermediates become a key step in Ti‐DHTP‐driven C─N coupling. Moreover, the more efficient *OCO intermediate inhibits the generation of large amounts of C‐bearing by‐products. Meanwhile, Ti‐DHTP has difficulty hydrogenating to form *COOH during the reduction of CO2 leading to the subsequent inability to produce *CO intermediates. This work reveals a new C─N coupling mechanism, which provides a feasible strategy for future research on the electrochemical synthesis of organic nitrogen‐bearing compounds. [ABSTRACT FROM AUTHOR]

Photocatalytic oxygen (O2) reduction to hydrogen peroxide (H2O2) is considered to be a promising method for energy storage. However, it suffers from the rapid recombination of carriers, the limited solubility and slow diffusion of O2, and the self‐decomposition of H2O2 in traditional diphase systems. Here, a self‐floating carbon dots/conjugated microporous polymer (CDs/CMP) photocatalytic system is established for H2O2 production and organic synthesis. Due to the D–π–A structure, porous structure, and hydrophobicity, CMP induced the intramolecular charge transfer, exposed abundant reaction sites, and enhanced O2 adsorption. CDs act as "bridges" for electron transmission and regulate the surface hydrophobicity of CMP, further improving charge transfer and optimizing the reaction interface. CDs/CMP system exhibits a high H2O2 production of 8542.6 µmol g−1 h−1 and concurrent furoic acid production at 2.22 mm h−1. This H2O2 production rate is ≈90% higher than that in the diphase system, exceeding all previously reported photocatalysts in triphase systems. Notably, the CDs/CMP system achieves the relative separation of the photocatalysts and H2O2, suppressing the generated H2O2 self‐decomposition. Theoretical calculations and in situ characterizations reveal the mechanism of H2O2 and furoic acid evolution. This self‐floating system provides insights into exploring the application of metal‐free photocatalysts in heterogeneous reactions. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of nitrate to ammonia (NO3RR) is a promising and eco‐friendly strategy for ammonia production. However, the sluggish kinetics of the eight‐electron transfer process and poor mechanistic understanding strongly impedes its application. To unveil the internal laws, herein, a library of Pd‐based bimetallene with various transition metal dopants (PdM (M=Fe, Co, Ni, Cu)) are screened to learn their structure–activity relationship towards NO3RR. The ultra‐thin structure of metallene greatly facilitates the exposure of active sites, and the transition metals dopants break the electronic balance and upshift its d‐band center, thus optimizing intermediates adsorption. The anisotropic electronic characteristics of these transition metals make the NO3RR activity in the order of PdCu>PdCo≈PdFe>PdNi>Pd, and a record‐high NH3 yield rate of 295 mg h−1 mgcat−1 along with Faradaic efficiency of 90.9 % is achieved in neutral electrolyte on PdCu bimetallene. Detailed studies further reveal that the moderate N‐species (*NO3 and *NO2) adsorption ability, enhanced *NO activation, and reduced HER activity facilitate the NH3 production. We believe our results will give a systematic guidance to the future design of NO3RR catalysts. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) using hydroxyl radicals (•OH) as oxidizing agents are a promising technology. Herein, a feasible strategy is developed to initially construct carbazole‐based D‐π‐A type conjugated polymer (PBNCZ) via the oxidative coupling. Additionally, introducing ─COO− through Cyano hydrolysis extends its conjugated structure and improves the energy band structure, which greatly facilitates the generation of •OH as well as the enrichment of pollutants. Detailed experiments and theoretical calculations have proved that the introduction of ─COO− enhances the adsorption of O2 and bisphenol A (BPA), optimizing the reaction path of •OH. Thus, it completely decomposes 10 ppm of BPA within just 10 min, exceeding all previously organic photocatalysts. Meanwhile, the efficiency of photocatalytic H2O2 production by PBNCZ‐COO− reaches 1719.03 µmol h−1 g−1 under visible light. This multifunctional material with high adsorption capacity, photodegradation efficiency, and photocatalytic H2O2 production activity provides a solid foundation for the preparation of organic photocatalysts. [ABSTRACT FROM AUTHOR]

With its efficient nitrogen fixation kinetics, electrochemical lithium‐mediated nitrogen reduction reaction (LMNRR) holds promise for replacing Haber–Bosch process and realizing sustainable and green ammonia production. However, the general interface problem in lithium electrochemistry seriously impedes the further enhancement of LMNRR performance. Inspired by the development history of lithium battery electrolytes, here, we extend the ring‐chain solvents coupling law to LMNRR system to rationally optimize the interface during the reaction process, achieving nearly a two‐fold Faradaic efficiency up to 54.78±1.60 %. Systematic theoretical simulations and experimental analysis jointly decipher that the anion‐rich Li+ solvation structure derived from ring tetrahydrofuran coupling with chain ether successfully suppresses the excessive passivation of electrolyte decomposition at the reaction interface, thus promoting the mass transfer of active species and enhancing the nitrogen fixation kinetics. This work offers a progressive insight into the electrolyte design of LMNRR system. [ABSTRACT FROM AUTHOR]

Solar‐driven photocatalytic conversion of carbon dioxide (CO2) into carbon‐neutral fuels is of significance for energy sustainability. The critical challenges in this process are high charge carrier recombination and low CO2 adsorption capacity. Here, by integrating porous covalent triazine frameworks (CTFs) with cadmium sulfide (CdS) nanospheres, a CdS@CTF‐HUST‐1 heterojunction photocatalyst with core–shell structure is developed for CO2‐to‐CO conversion. Experimental investigations combined with density functional theory simulations reveal that the formation of an internal electric field provides the driving force for accelerating S‐scheme charge transfer, resulting in enhanced separation and utilization efficiency of charge carriers in photocatalysis. Together with the improved CO2 adsorption capacity contributed by the porous structure of the CTF‐HUST‐1 shell, the CdS@CTF‐HUST‐1 heterojunction photocatalyst gives an impressive CO yield rate of 168.77 µmol g−1 h−1 with high selectivity. This research furnishes a feasible strategy to construct highly active core–shell composite photocatalysts for optimizing CO2 adsorption and conversion. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction offers a sustainable alternative to the conventional Haber‐Bosch process. However, it is currently restricted by low effective overpotential due to the concentration polarization, which arises from accumulated products, ammonium, at the reaction interface. Here, a novel covalent organic polymer with ordered periodic cationic sites is proposed to tackle this challenge. The whole network exhibits strong positive charge and effectively repels the positively charged ammonium, enabling an ultra‐low interfacial product concentration, and successfully driving the reaction equilibrium to the forward direction. With the given potential unchanged, the suppressed overpotential can be much liberated, ultimately leading to a continuous high‐level reaction rate. As expected, when this tailored microenvironment is coupled with a transition metal‐based catalyst, a 24‐fold improvement is generated in the Faradaic efficiency (73.74 %) as compared with the bare one. The proposed strategy underscores the importance of optimizing dynamic processes as a means of improving overall performance in electrochemical syntheses. [ABSTRACT FROM AUTHOR]

Converting CO2 into high‐value C2 chemicals such as acetate with high selectivity and efficiency is a critical issue in renewable energy storage. Herein, for the first time we present a vibration‐driven piezocatalysis with tin(II) monosulfide (SnS) nanobelts for conversion of CO2 to acetate with 100 % selectivity, and the highest production rate (2.21 mM h−1) compared with reported catalysts. Mechanism analysis reveal that the polarized charges triggered by periodic mechanical vibration promote the adsorption and activation of CO2. The electron transfer can be facilitated due to built‐in electric field, decreased band gap and work function of SnS under stress. Remarkably, reduced distance between active sites leads to charge enrichment on Sn sites, promoting the C−C coupling, reducing the energy barriers of the rate determining step. It puts forward a bran‐new strategy for converting CO2 into high‐value C2 products with efficient, low‐cost and environment‐friendly piezocatalysis utilizing mechanical energy. [ABSTRACT FROM AUTHOR]

This study proposes the construction of porous nanomaterial (HOFs@Fe3+) which anchors non‐noble metal ions Fe3+ onto nanoscale rod‐like hydrogen‐bonded organic frameworks (HOFs) by electrostatic and coordination interactions. The high specific surface area and the abundance of hydrogen‐bond adsorption active sites in pore structure of HOFs@Fe3+ facilitate strong interactions with the double OH in bisphenol A (BPA), resulting in the highest saturation adsorption of BPA that has been reported so far (452 mg g‐1). In addition, the ordered conjugate stacking framework structure and hydrogen bond of HOFs@Fe3+ and the variable valence properties of Fe3+ create new pathways for efficient separation of photogenerated carriers. The results show that HOFs@Fe3+ can completely adsorb and photodegrade 50 ppm BPA within 20 min, owing to the abundant hydrogen bond that acts both as adsorption sites to accelerate the mass transfer process and as catalytic sites to ensure adsorption and photodegradation can be matched synergistically. Meanwhile, the efficiency of photocatalytic H2 production by HOFs@Fe3+ reaches 21.55 mmol g‐1 h‐1 with non‐noble metal Fe3+ as co‐catalyst. This tri‐functional material with high adsorption capacity, high photodegradation efficiency, and high photocatalytic H2 production activity can be successfully used to solve the long‐standing conflict between environment and energy. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is one of the biggest threats to the environment and health. AMR rapidly invalidates conventional antibiotics, and antimicrobial nanomaterials have been increasingly explored as alternatives. Interestingly, several antimicrobial nanomaterials show AMR‐independent antimicrobial effects without detectable new resistance and have therefore been suggested to prevent AMR evolution. In contrast, some are found to trigger the evolution of AMR. Given these seemingly conflicting findings, a timely discussion of the two faces of antimicrobial nanomaterials is urgently needed. This review systematically compares the killing mechanisms and structure‐activity relationships of antibiotics and antimicrobial nanomaterials. We then focus on nano‐microbe interactions to elucidate the impacts of molecular initiating events on AMR evolution. Finally, we provide an outlook on future antimicrobial nanomaterials and propose design principles for the prevention of AMR evolution. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 (CO2RR) and nitrogen (NRR) constitute alternatives to fossil fuel‐based technologies for the production of high‐value‐added chemicals. Yet their practical application is still hampered by the low energy and Faradaic efficiencies although numerous efforts have been paid to overcome the fatal shortcomings. To date, most studies have focused on designing and developing advanced electrocatalysts, while the understanding of electrolyte, which would significantly influence the reaction microenvironment, are still not enough to provide insight to construct highly active and selective electrochemical systems. Here, a comprehensive review of the different electrolytes participating in the CO2RR and NRR is provided, including acidic, neutral, alkaline, and water‐in‐salt electrolyte as aqueous electrolytes, as well as organic electrolyte, ionic‐liquids electrolyte, and the mixture of the two as non‐aqueous electrolytes. Through the discussion of the roles of these various electrolytes, it is aimed to grasp their essential function during the electrochemical process and how these functions can be used as design parameters for improving electrocatalytic performance. Finally, priorities for future studies are suggested to support the in‐depth understanding of the electrolyte effects and thus guide efficient selection for next‐generation gas‐involving electrochemical reactions. [ABSTRACT FROM AUTHOR]

Copper is a key metal for carbon dioxide (CO2) reduction reaction, which can reduce CO2 to value‐added products. The core‐shell structure can effectively promote the C−C coupling process due to its strong synergistic effect originated from its unique electronic structure and interface environment. Therefore, the combination of copper and core‐shell structure to design an efficient Cu‐based core‐shell structure catalyst is of great significance for electrocatalytic CO2 reduction (CO2RR). In this review, we first briefly summarize the basic principle of CO2RR. In addition, we outline the advantages of core‐shell structure for catalysis. Then, we review the recent research progresses of Cu‐based core‐shell structures for the selective reduction of multi‐carbon (C2+) products. In the end, the challenges of using core‐shell catalyst for CO2RR are described, and the future development of this field is prospected. [ABSTRACT FROM AUTHOR]

Low mass‐transfer efficiency and reaction‐driving force make it difficult to realize thorough purification in traditional low‐concentration pollutant treatments. Herein, we propose an "adsorption/catalysis in situ" perylene based bifunctional micelle for efficient, accurate and rapid adsorption and catalytic degradation of low‐concentration bisphenol A (BPA). They show super‐fast (within 10 s), high capacity (448 mg g−1) and selectivity for BPA adsorption, due to π–π, hydrophobic interactions and hydrogen bonding. The BPA degradation efficiency improves by up to 8 times after forming micelles compared with simple perylene nanorods, which is primarily due to the superior mass‐transfer from adsorption. Moreover, self‐assembly can optimize the stacking of the perylene moieties and facilitate charge transfer in micelle, and the regular π–π stacking of inside perylene units enhances the response to visible light, resulting in high catalytic capacity and good cycling stability. [ABSTRACT FROM AUTHOR]

Capturing radioactive iodomethane and its vapors is a major challenge due to its low adsorption capacity. Herein, we have developed for the first time a pyridine‐entrapped elastic crosslinked polysulfate gel (pyridine/TPC‐cPS) as an efficient absorbent for iodomethane capture. Each pyridine‐encased TPC‐cPS network cell acts as a mini‐reactor for salt formation between pyridine and iodomethane. The yield reaches up to 96.65 % and traps saturated iodomethane vapor of 1.573 g gpyridine/TPC‐cPS−1 (equivalent to 18.103 g gTPC‐cPS−1), which is the highest capacity reported to date. Both experiments and molecular dynamics simulations reveal that the unusual adsorption of polysulfate for polar aprotic organics can be attributed to the fact that the electrostatic interactions between the polar group (O=S=O) in the polymer backbone and the polar groups in the organic molecules fixed the solvent in the polymer matrix, while the van der Waals forces between the nonpolar groups in the polymer and molecules induced swelling. [ABSTRACT FROM AUTHOR]

Organic semiconductor devices with low energy consumption and excellent stability are highly desirable. Controlling the intermolecular alignment orientation by designing the molecular structure or optimization of the film preparation process is an alternative way to achieve this goal. In this paper, a new idea was proposed to realize the formation of an aligned monomolecular layer and multimolecular layer thin films on the electrode substrate by controlling the surface pressure of molecular layer on the liquid surface by LB technology. An amphiphilic π‐conjugated D−A molecule was synthesized, and the influence of spin coating and LB technology on intermolecular ordered stacking in the film and the electrical memory performance were investigated. The results demonstrated that the film fabricated by LB technology has some advantages compared with that fabricated by spin‐coating method, such as higher crystallinity, lower surface roughness and better‐organized monomolecular and multimolecular layer, which significantly promoted the performance of the electrical memory device with lower power consumption and longer stability. [ABSTRACT FROM AUTHOR]

Two small molecular monomers, ph‐TPE and ph‐TPE‐CN, and their homopolymers Poly (ph‐TPE) and Poly (ph‐TPE‐CN) containing tetra phenylethylene and sulfate structures, were synthesized by a sulfur (VI) fluorine exchange click reaction (SuFEx) and radical polymerization. All the monomers and polymers exhibit a typical aggregation‐induced emission (AIE) effect both in the solid state and aggregated state. Moreover, based on the intermolecular charge transfer (ICT) effect between the tetra phenylethylene chromophore and p‐nitrophenol, both polymers could be used for the selective detection of p‐nitrophenol. The detection limit and reactivity coefficient of Poly (ph‐TPE) are 0.081 μM and 5.15×104 M−1, respectively, whereas the detection limit and reactivity coefficient of Poly (ph‐TPE‐CN) are 0.077 μM and 1.81×104 M−1, respectively. This can be attributed to the greater sensitivity of Poly (ph‐TPE‐CN) to p‐nitrophenol than that of Poly (ph‐TPE). This work provides a new methodology for the preparation and broadening application of side‐chain type AIE‐active polysulfate fluorescent probes. [ABSTRACT FROM AUTHOR]

The catalytic room temperature oxidation of formaldehyde (HCHO) is widely considered as a viable method for the abatement of indoor toxic HCHO pollution. Herein, Pt/MnO2 nanoflowers anchored to boron nitride aerogels (Pt/MnO2‐BN) were fabricated for the catalytic room temperature oxidation of HCHO. The three‐dimensional Pt/MnO2‐BN aerogels demonstrated superior catalytic activity as a result of the improved diffusion of the reactant molecules within the porous structure. Furthermore, the porous aerogels displayed excellent HCHO adsorption capacities, which promote a rapid HCHO gas‐phase concentration reduction and a subsequent complete oxidation of the adsorbed HCHO. The combined adsorption and oxidation properties of the Pt/MnO2‐BN aerogels enhance the oxidative removal of HCHO. The optimized Pt/MnO2‐BN demonstrated excellent catalytic activity toward HCHO (200 ppm) at room temperature, achieving a 96 % formaldehyde conversion after 50 min. [ABSTRACT FROM AUTHOR]

Molecules showing mechanochromic luminescence (MCL) are promising for use in the in the fields of sensing and probes. We report the design and synthesis of new naphthalimide‐based hydrazone derivatives, NI‐TPE and NI‐3BA. Both the luminogens are weakly emissive with sΦf=0.3 % and 0.5 % respectively when aggregated in amorphous states as strong π‐π stacking and intermolecular interaction prevent luminescence. On the contrary, in the crystalline state, single crystal analysis of two derivatives shows that nonradiative decay is reduced or inhibited by molecular stacking modes and intermolecular interactions. Increases of fluorescence emission intensity to sΦf=5.5 % and 6.0 % upon solvent evaporation are attributed to weak π‐π overlapping and hydrogen bonding (N−H ⋅⋅⋅ O, distance 2.99 Å), which are beneficial to the formation of molecules with a loose packing. At the same time, the packing modes that the two derivatives adopt in the crystal lattice are destroyed to result in a low solid‐state fluorescence quantum yield and a bathochromic shift of 23–25 nm upon grinding. All these factors cause the two derivatives show an unusual "turn off" MCL phenomenon. The fluorescence emission, its pH reversibility, and selective response to fluoride and acetate ions of up to 91–93 % in dilute solutions were also demonstrated. [ABSTRACT FROM AUTHOR]

With the rapid development of data‐driven human interaction, advanced data‐storage technologies with lower power consumption, larger storage capacity, faster switching speed, and higher integration density have become the goals of future memory electronics. Nevertheless, the physical limitations of conventional Si‐based binary storage systems lag far behind the ultrahigh‐density requirements of post‐Moore information storage. In this regard, the pursuit of alternatives and/or supplements to the existing storage technology has come to the forefront. Recently, organic‐based resistive memory materials have emerged as promising candidates for next‐generation information storage applications, which provide new possibilities of realizing high‐performance organic electronics. Herein, the memory device structure, switching types, mechanisms, and recent advances in organic resistive memory materials are reviewed. In particular, their potential of fulfilling multilevel storage is summarized. Besides, the present challenges and future prospects confronted by organic resistive memory materials and devices are discussed. [ABSTRACT FROM AUTHOR]

Molecular stacking and crystallinity in a film can effectively affect the charge‐carrier mobility of semiconductor materials and corresponding device performance. Currently, solvent vapor annealing (SVA), as an effective thin‐film optimization strategy, which can select the appropriate solvent according to the characteristics of the molecular structure to optimize the intermolecular orderly arrangement, is often adopted. Thus, a small conjugated molecule C20‐ID(TPCN)2 with flexible alkyl side chains was synthesized and applied as active layer of sandwich memory devices. The active layer film has been annealed with different polar solvent vapors to evaluate the relationship among the molecular structure, solvent selection, annealing parameters and intermolecular stacking. Compared to un‐annealed devices, the memory devices based on the films through CH2Cl2‐annealing show better performance with a lower threshold voltage due to developed ordered molecular aggregation and better crystallinity, while a hydrophilic solvent vapor will weaken the device performance. This work not only reveals that selecting an appropriate solvent vapor for the molecular structure could be of vital importance in inducing the desired intermolecular stacking mode, but also provides a novel insight for the realization of organic semiconductor devices with excellent performance. [ABSTRACT FROM AUTHOR]

Visible‐light‐responsive hierarchical Co9S8/ZnIn2S4 tubular heterostructures are fabricated by growing 2D ZnIn2S4 nanosheets on 1D hollow Co9S8 nanotubes. This design combines two photoresponsive sulfide semiconductors in a stable heterojunction with a hierarchical hollow tubular structure, improving visible‐light absorption, yielding a large surface area, exposing sufficient catalytically active sites, and promoting the separation and migration of photogenerated charges. The hierarchical nanotubes exhibit excellent photocatalytic H2 evolution and CrVI reduction efficiency. Under visible‐light illumination, the optimized Co9S8/ZnIn2S4 heterostructure provides a remarkable H2 generation rate of 9039 μmol h−1 g−1 without the use of any co‐catalysts and CrVI is completely reduced in 45 min. The Co9S8/ZnIn2S4 heterostructure is stable after multiple photocatalytic cycles. [ABSTRACT FROM AUTHOR]

BiOBr containing surface oxygen vacancies (OVs) was prepared by a simple solvothermal method and combined with graphitic carbon nitride (g‐C3N4) to construct a heterojunction for photocatalytic oxidation of nitric oxide (NO) and reduction of carbon dioxide (CO2). The formation of the heterojunction enhanced the transfer and separation efficiency of photogenerated carriers. Furthermore, the surface OVs sufficiently exposed catalytically active sites, and enabled capture of photoexcited electrons at the surface of the catalyst. Internal recombination of photogenerated charges was also limited, which contributed to generation of more active oxygen for NO oxidation. Heterojunction and OVs worked together to form a spatial conductive network framework, which achieved 63 % NO removal, 96 % selectivity for carbonaceous products (that is, CO and CH4). The stability of the catalyst was confirmed by cycling experiments and X‐ray diffraction and transmission electron microscopy after NO removal. [ABSTRACT FROM AUTHOR]

Precious‐metal catalysts (e.g., Au, Rh, Ag, Ru, Pt, and Pd) supported on transition‐metal oxides (e.g., Al2O3, Fe2O3, CeO2, ZrO2, Co3O4, MnO2, TiO2, and NiO) can effectively oxidize volatile organic compounds. In this study, porous platinum‐supported zirconia materials have been prepared by a "surface‐casting" method. The synthesized catalysts present an ordered nanotube structure and exhibited excellent performance toward the catalytic oxidation of formaldehyde. A facile method, utilizing a boiling water bath, was used to fabricate graphene aerogel (GA), and the macroscopic 3D Pt/ZrO2‐GA was modified by introducing an adjustable MOF coating by a surface step‐by‐step method. The unblocked mesoporous structure of the graphene aerogel facilitates the ingress and egress of reactants and product molecules. The selected 7 wt.% Pt/ZrO2‐GA‐MOF‐5 composite demonstrated excellent performance for HCHO adsorption. Additionally, this catalyst achieved around 90 % conversion when subjected to a reaction temperature of 70 °C (T90 %=70 °C). The Pt/ZrO2‐GA‐MOF‐5 composite induces a catalytic cycle, increasing the conversion by simultaneously adsorbing and oxidizing HCHO. This work provides a simple approach to increasing reactant concentration on the catalyst to increase the rate of reaction. [ABSTRACT FROM AUTHOR]

A triphenylamine derivative decorated with an azobenzene group (TDA) was synthesized via a SuFEx click reaction and its polymer, poly(triphenylamine) (PTDA), was polymerized through a redox polymerization. More interestingly, its polymeric metal complex, PTDA‐Fe, can be simply obtained via one‐pot reaction between TDA and FeCl3 owing to TDA showing a strong affinity to the FeIII ion. The sandwich memory device based on PTDA nanofilms as active layers exhibited a binary memory performance. However, the memory device based on its polymeric metal complex exhibited a unique ternary memory behavior. The different memory performances should come from the different conductive mechanism. The mechanism of such ternary memory devices is illustrated based on both the theoretical calculation and experiments. Our work provides new insights into the preparation of novel materials for multilevel memory devices. [ABSTRACT FROM AUTHOR]

Toxic gases that are colorless and odorless, such as CO, are a major environmental concern and require early detection to prevent serious toxicological effects. In this study, a unique system (Pt/HMSs‐BRC) was fabricated by combining a catalyst (Pt/hollow mesoporous silica spheres, Pt/HMSs) with a silica gel containing an adsorbed chromogenic probe (binuclear rhodium complex, BRC). The process is a simple method to prepare well‐dispersed and uniform Pt nanoparticles. The Pt/HMSs‐BRC materials demonstrated early CO detection and excellent catalytic performance for CO oxidation. The probe exhibited remarkable color modulation from gray‐violet to light‐yellow when exposed to CO concentration levels above 50 ppm, and the color of the chromogenic probe was fully recoverable. By a kinetics‐assisted discrimination method and DFT calculations, it was found that the corner Pt sites are the dominant active sites for CO oxidation. [ABSTRACT FROM AUTHOR]

Porous carbon (PC) materials with high surface area can separate electron–hole pairs and adsorb organic pollutants more effectively. A series of nanocomposites were prepared by anchoring black TiO2 nanoparticles (BTN) onto PC through a calcination process. Chemical and structural features of samples were examined by X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy, powder X‐ray diffraction (P‐XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. The resulting adsorption‐photocatalysis synergistic effect led to a dramatically improved photocurrent for BTN@PCs, thus indicating the high photocatalytic performance toward water‐soluble organic species. For instance, the degradation of tetracycline under visible light reached 90 %, which is higher than that for activated carbon doped onto BTN (57 %) without any additional agents. Moreover, the degradation of other antibiotics (such as oxytetracycline and ciprofloxacin) and methylene blue were also studied, thus showing that this system has the potential to be used for water treatment. [ABSTRACT FROM AUTHOR]

Catalytic performance is heavily dependent on how the structures of nanomaterials are designed. Co3O4–CeO2 composite nanotubes with open ends and mesoporous structures were fabricated through a facile and environmentally friendly reaction. The mesoporous Co3O4 nanotubes were synthesized by the calcination of cobalt–aspartic acid (Co–Asp) nanowires and coated with a CeO2 shell. The composite nanotubes were characterized by SEM, TEM, XRD, and X‐ray photoelectron spectroscopy. The composite materials comprise a combination of Co3O4 nanotubes and CeO2 nanoparticles with a hollow and mesoporous bimetallic oxide structure. The large BET surface area led to a higher degree of accessible active sites compared with other Co3O4–CeO2 composite nanomaterials with other structures. The resulting Co3O4–CeO2‐26.3 wt % composite nanotubes, with a CeO2 content of approximately 26.3 wt %, achieved 100 % CO conversion at 145 °C. Additionally, the synergistic effect between the two metal oxides comprising the Co3O4–CeO2 composite nanotubes was demonstrated by the enhanced catalytic activity compared with pure Co3O4 nanotubes and CeO2 nanoparticles. Hollow. I can see through you! A facile strategy to fabricate high‐quality Co3O4–CeO2 composite nanotubes with open ends and mesoporous structures is developed. The resulting Co3O4–CeO2‐26.3 wt % composite nanotubes, with a CeO2 content of approximately 26.3 wt %, achieved 100 % CO conversion at 145 °C. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP), a star‐shaped two‐dimensional material, has attracted considerable attention owing to its unique chemical and physical properties. BP shows great potential in photocatalysis area because of its excellent optical properties; however, its applications in this field have been limited to date. Now, a Z‐scheme heterojunction of 2D/2D BP/monolayer Bi2WO6 (MBWO) is fabricated by a simple and effective method. The BP/MBWO heterojunction exhibits enhanced photocatalytic performance in photocatalytic water splitting to produce H2 and NO removal to purify air; the highest H2 evolution rate of BP/MBWO is 21042 μmol g−1, is 9.15 times that of pristine MBWO and the NO removal ratio was as high as 67 %. A Z‐scheme photocatalytic mechanism is proposed based on monitoring of.O2−,.OH, NO2, and NO3− species in the reaction. This work broadens applications of BP and highlights its promise in the treatment of environmental pollution and renewable energy issues. A Z‐scheme heterojunction of 2D/2D black phosphorus/monolayer Bi2WO6 was fabricated with enhanced photocatalytic performance under visible light irradiation. The highest NO removal ratio was up to 67 % and the H2 evolution ratio 21 042 μmol g−1. The black phosphorus nanosheets can be used for photocatalytic degradation of exhaust gases in air. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Tetracycline (TC) and other antibiotics accumulated in groundwater and soil pollute ecological environment and threaten human health. Gold nanoparticles doped on photocatalysts are able to enhance the photodegradation efficiency during removing these antibiotics, but preparation of Au nanoparticles of well‐dispersion on photocatalysts remains challenging. In this work, zeolite imidazolate (ZIF‐8) was employed as the precursor to prepare Au@ZnO photocatalyst via impregnation and in‐situ reduction method to efficiently degrade the tetracycline in the aqueous solution. Au nanoparticles are of 10 nm in size and uniformly dispersed on the surfaces of ZnO microstructures. The as‐prepared Au@ZnO is able to remove 85.5% of TC of 0.010 mg/mL within 2 h, presenting higher photocatalytic activity than pure ZnO catalyst. Most importantly, the catalyst shows its superior stability after five cycles without structure and activity changing. The mechanism of the photocatalytic degradation was discussed in detail. Zeolitic imidazolate framework 8‐derived Au@ZnO for photocatalytic degradation of tetracycline. [ABSTRACT FROM AUTHOR]

Photocatalysis is an efficient approach to degrade hydrogen sulfide (H2S) and titanium dioxide (TiO2) is commonly used as a catalyst for H2S degradation. However, the low separation rate of photoinduced carriers and low gas adsorption ability of TiO2 limit its H2S photocatalytic decomposition rate. In this paper, single‐crystalline TiO2 nanowires are assembled on one‐dimensional carbon nanofibers (CNFs) and a tunable metal–organic framework (MOF) coating is fabricated on the surface of the TiO2 nanowires using a versatile step‐by‐step self‐assembly strategy. The excellent photocatalytic properties of the resulting membrane originate from the ability of the CNFs to rapidly transport charge carriers and the high and regenerable H2S adsorption ability of the MOF. The photocatalytic mechanism of the as‐prepared material was also discussed. Therefore, this work provides a promising method to improve the photocatalytic performance of H2S degradation. Insane in the membrane: A carbon nanofiber/TiO2 nanowire/MIL‐100 (denoted as CTWM) membrane was prepared as a photocatalyst that allowed the simultaneous adsorption and catalysis of H2S. The MIL‐100 MOF coated on the surface of the TiO2 nanowires in the CTWM membrane enhanced its photocatalytic activity by increasing its H2S adsorption ability. In addition, the carbon nanofiber (CNF)‐supported material displayed rapid transport of charge carriers and favourable recycling characteristics. [ABSTRACT FROM AUTHOR]

Abstract: The diverse functionalities of large N‐heteroacenes continue to be developed in terms of their strategic synthesis and application in the organic electronic field. Here, we report a novel large stable pyrene‐containing N‐heteroacene with ten linearly‐annulated rings in one row. Remarkably, it exhibited excellent tri‐state resistive memory property, which held great promise to achieve ultrahigh‐density data storage. To the best of our knowledge, it is the first demonstration of organic multistate memory device based on large N‐heteroacene (n≥10), which provides guidelines for designing more proof‐of‐concept larger N‐heteroacene‐based memory electronics. [ABSTRACT FROM AUTHOR]

Abstract: The molecular stacking in film state has been confirmed to have an important influence on electronic properties of organic semiconductors. Thus, how to improve the molecular stacking and the corresponding device performance through molecular design is a difficult question that researches want to figure out. In this work, three small molecules with different bridge‐spacers, phenyl ring, pyridine, and pyrimidine, are designed to study the effect of nitrogen amount on molecular stacking in film state. The infrared spectroscopy in solution and film states are first measured to consider the hydrogen bond between the neighboring molecules, which can induce ordered molecular stacking through intermolecular interaction. X‐ray diffraction, atomic force microscopy, and grazing incidence small angle X‐ray scattering measurements confirm the ordered molecular stacking and crystalline orientation of nitrogenous heterocycles substituted molecules in film state. Additionally, nitrogenous heterocycles substituted molecules exhibit the excellent ternary data‐storage properties with low threshold voltage and high current ratio. This result presents the strategy for designing novel small molecules with excellent molecular stacking in film state. [ABSTRACT FROM AUTHOR]

Abstract: Precious metals (Au and Pt) loaded in a mesoporous substrate (carbon and silicon) are popular materials for catalytic CO oxidation. However, the preparation of noble metals and the metal particle size after deposition in the pore channels of the mesoporous materials are serious issues for environmentally friendly applications. Herein, a gold‐decorated hollow porous carbon nanospheres (Au/HPCN) catalyst, which is both durable and uniform, is synthesized by a facile in situ reduction route for continuous CO oxidation. In our approach, HPCNs were selected as the substrate because of their thermal stability, well‐defined nanostructure, and large surface area. Au nanoclusters were loaded in the pore channels of HPCN because of their stability and catalytic performance. The as‐synthesized nanocomposite possesses a uniform size and highly porous structure. Moreover, CO oxidation occurred both during the reduction of Au3+ ions and after the preparation of Au/HPCN. [ABSTRACT FROM AUTHOR]

Herein, novel random copolymers PMNN and PMNB were designed and synthesized, and the memory devices Al/ PMNN and PMNB/ITO both exhibited ternary memory performance. The switching voltages of the OFF-ON1 and ON1-ON2 transitions for both memory devices are around −2.0 and −3.5 V, respectively, and the ON1/OFF, ON2/ON1 current ratios are both up to 103. The observed tristable electrical conductivity switching could be attributed to field-induced conformational ordering of the naphthalene rings in the side chains, and subsequent charge trapping by 1,8-naphthalimide moieties. More interestingly, by adjusting the connection sites of 1,8-naphthalimide moieties to tune the steric-twist effect, different memory properties were achieved ( PMNN showed nonvolatile write once, read many (WORM) memory behavior, whereas PMNB showed volatile static RAM (SRAM) memory behavior). This result will offer a guideline for the design of different high-performance multilevel memory devices by tuning the steric effects of the chemical moieties. [ABSTRACT FROM AUTHOR]

Smart surfaces with controllable wettability have attracted substantial interest owing to the potential use of these materials for the separation of oil from oily water caused by frequent oil-spill accidents. Because there are few separation materials on the market that are capable of switching between hydrophobicity and hydrophilicity, this work reports an efficient and low-cost method to fabricate a photoresponsive membrane through the sulfur(VI) fluoride exchange reaction (SuFEx) between poly(4-vinylphenol sulfofluoridate) and ( E)-1-(4-( tert-butoxy)phenyl)-2-(4-(trifluoromethoxy)phenyl)diazene. The resulting material displays switchable wettability between hydrophobic and hydrophilic states when subjected to ultraviolet or visible irradiation. This membrane can be recycled (greater than five times) and features superior efficiency (up to 97.9 %) for the separation of oils that have both higher and lower densities than water. This work is the first proof-of-concept application of SuFEx to fabricate functional materials for environmental remediation. [ABSTRACT FROM AUTHOR]

The SuFEx-based polycondensation between bisalkylsulfonyl fluorides (AA monomers) and bisphenol bis( t-butyldimethylsilyl) ethers (BB monomers) using [Ph3P=N−PPh3]+[HF2]− as the catalyst is described. The AA monomers were prepared via the highly reliable Michael addition of ethenesulfonyl fluoride and amines/anilines while the BB monomers were obtained from silylation of bisphenols by t-butyldimethylsilyl chloride. With these reactions, a remarkable diversity of monomeric building blocks was achieved by exploiting readily available amines, anilines, and bisphenols as starting materials. The SuFEx-based polysulfonate formation reaction exhibited excellent efficiency and functional group tolerance, producing polysulfonates with a variety of side chain functionalities in >99 % conversion within 10 min to 1 h. When bearing an orthogonal group on the side chain, the polysulfonates can be further functionalized via click-chemistry-based post-polymerization modification. [ABSTRACT FROM AUTHOR]

Owing to the demands of state-of-the-art information technologies that are suitable for vast data storage, the necessity for organic memory device (OMD) materials is highlighted. However, OMDs based on metal complexes are limited to several types of transition-metal complex systems containing nitrogen-donor ligands. Herein, attempts are made to introduce novel alkynylgold(III) materials into memory devices with superior performance. In this respect, an alkynyl-containing coumarin gold(III) complex, [(C19N5H11)Au−C≡C−C9H5O], has been synthesized and integrated into a sandwiched Al/[(C19N5H11)Au−C≡C−C9H5O]/indium tin oxide device. By precisely controlling the compliance current ( Icc), the devices show different switching characteristics from flash-type binary resistance switching ( Icc≤10−3 A) to WORM-type (WORM=write once read many times) ternary resistance switching ( Icc=10−2 A). This work explores electrical gold(III) complex based memories for potential use in organic electronics. [ABSTRACT FROM AUTHOR]

Organic electronic memory devices have become one of the most important candidates for the 'next generation' of information-storage devices. Herein, a polymer (PA-m-Ph), which contained electron-donor/-accepter groups in the main chain and a carbazole group in the side chain, was prepared and investigated as a new electrical memory material. Three polymer films (PA-m-Ph-90, PA-m-Ph-200, and PA-m-Ph-290) were obtained by using different annealing temperatures (90, 200, and 290 °C, respectively). The resulting ITO/PA-m-Ph-90/Al memory device exhibited ternary memory performance, thus indicating that there were three stable conductivity states in the conduction process. The ITO/PA-m-Ph-200/Al device could endure the higher annealing temperature (200 °C) and maintained a similar ternary performance. However, ternary behavior was not observed in the I- V curve of the ITO/PA-m-Ph-290/Al device. We verified that the heating process could lessen the configurational distortion of the carbazole group and affected the stability of the intermediate conductivity state of these ternary memory devices. [ABSTRACT FROM AUTHOR]