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Lithium sulfur battery is one of the most promising applicants for the next generation of energy storage devices whose commercial applications are impeded by the key issue of shuttle effect. To overcome this obstacle, various of two-dimensional (2D) carbon-based metal-free compounds have been proposed to serve as anchoring materials for immobilizing soluble lithium polysulfides (LiPs), which however suffered from low electronic conductivity implying unsatisfactory performance for catalyzing sulfur redox. Therefore, we predicted metallic C5N monolayers, possessing hexagonal (H) and orthorhombic (O) phases, which exhibit excellent performances for suppressing the shuttle effect. First principles simulations demonstrate that O-C5N could serve as bifunctional anchoring material due to its strong adsorption capability to LiPs and excellent catalytic performance for sulfur redox with active sites from both basal plane and zigzag edges. Furthermore, the rate of Li2S oxidation over O-C5N is fast due to low energy barrier of 0.93eV for Li2S decomposition. While for H-C5N only N atoms locating at the armchair edges can efficiently trap LiPs and boost the formation and dissociation of Li2S during discharge and charge processes, respectively. The current work opens an avenue of designing 2D metallic carbon-based anchoring materials for Lithium sulfur battery, which deserves further experimental research efforts.

An environmentally benign, cost-efficient and practical methodology for the room temperature synthesis of 2-arylacetophenones in water has been discovered.

A facile and efficient oxidative functionalization of vinyl azides with aldehydes furnishing a diverse array of β-acylated enaminones was developed.

Rechargeable zinc-based batteries (RZBs) using low-cost zinc metal anodes are feasible for large-scale energy storage, but the developments currently are restricted by the poor performances. Here we constructed a particular dual-ion battery (DIB) based on zinc hexacyanoferrate (ZnHCF) cathode, zinc metal anode, and non-aqueous K+/Zn2+ hybrid ions electrolyte. It was revealed that K+-ions occupied almost all the cavities in ZnHCF at high voltage over 1.7 V (vs. Zn2+/Zn), which effectively blocked Zn2+-ions insertion. The ZnHCF showed a zero-strain characteristic during the repeated K+-ions intake/removal. Meanwhile, the charge screening effect of additive K+-ions on optimizing the zinc electrodeposition process ensured the reversible and dendrite-free Zn plating/stripping. The DIBs demonstrated excellent rate performances (57 and 47 mAh gcathode‒1 at 2000 and 5000 mA g‒1, respectively) and incredibly 100,000-cycles life with 74% capacity retention.

Responsive Pickering emulsions exhibit promising application in industry owing to the integration of the high storage stability with on-demand demulsification. In this study, stimuli-responsive Pickering emulsions stabilized by poly[oligo(ethylene glycol) methyl ether methacrylate]15-b-poly(diacetone acrylamide)120 (E15D120) worms were indicated, in which E15D120 worms were prepared via reversible addition-fragmentation chain transfer-based aqueous dispersion polymerization using thermo-sensitive POEGMA15 as both the stabilizer block and macro-chain transfer agent. The factors influencing the morphologies of copolymers during polymerization-induced self assembly have been investigated. A series of different morphological polymer nanoparticles including spheres, worms, and vesicles could be produced through rational synthesis. E15D120 worms demonstrated excellent emulsifying performances and could be used as emulsifiers to form n-dodecane-in-water Pickering emulsions at a low content. The formed n-dodecane-in-water Pickering emulsions revealed a slow demulsification at pH 10 or 70 °C or pH 10/70 °C combinations, and several hours were needed for the demulsification of Pickering emulsions. However, n-dodecane-in-water Pickering emulsions displayed a rapid demulsification (∼10 min) at an elevated temperature, such as 90 °C. The different demulsification rates were attributed to different sensitivities of E15D120 worms to external stimuli. Pickering emulsions integrating a rapid responsive demulsification with a slow one would be well satisfactory on different occasions.

The two-step strategy screening based high throughput calculation is an effective method to search for highly active single atom catalysts (SACs) for efficient nitrogen reduction reaction (NRR), sharing a common feature of active metal centers MN4. However, this method faces the lack of descriptor for designing SACs due to limited data. Herein we proposed a robust empirical rule to estimate 312 credible limiting potentials for NRR over 104 C3N-supported SACs. It is found that the limiting potential scales clearly with the adsorption free energies of two key reaction intermediates (∗N2H and ∗NH2), which are significantly dependent on the structure relating descriptor φ, and the activity of SACs with and without N coordination exhibits similar catalytic efficiency. We identified four high-performance SACs having moieties of CrC2N2, CrC4, MnC4 and OsC4 with high selectivity towards NRR and competitive limiting potentials of −0.40, −0.45, −0.53 and −0.54 V, respectively. The φ values for these four SACs are around 19–25 which fall within its optimal ranges of 20–25 validating its prediction fidelity. This work broadens the discovery of two-dimensional carbon-nitrides supported SACs free of N coordination towards efficient N2 reduction and opens a new route of descriptor-guided design of efficient SACs for electrocatalysis process.

A strategy for catalyst-free domino reaction of 4-aminopyridin-2(1H)-ones, arylglyoxal hydrates and different 1,3-dicarbonyl compounds in water has been established. The mild and efficient procedure afforded pyrrolo[3,2-c]pyridine derivatives with 76–94% yields after simple crystallization. The present procedure shows promising characteristics, such as readily available starting materials, the use of water as reaction media, simple and efficient one-pot operation, and avoiding the need for any hazardous or expensive catalysts.

Nonaqueous Pickering emulsions exhibit promising applications in many industrial areas but have been relatively less studied in the past. In this study

Photoelectrochemical oxygen reduction reaction (ORR) toward H2O2 is highly desirable because only sunlight, O2 and water are required in the process. However, the corresponding studies are still at its infancy because of the lack of suitable photocathodes, especially inorganic semiconductor photocathodes. In this work, we report CuBi2O4/CuO (CBO/CuO) heterojunction submicrocrystalline film photocathodes with efficient ORR activity for H2O2 production. The heterojunction film photocathodes were prepared through thermal evaporation of Cu and Bi metals under vacuum and subsequent annealing treatment. Furthermore, the doping of Gd3+ ions into CBO/CuO could significantly enhance the yield of H2O2. As a result, the concentration of H2O2 could reach 1.3 mM within 30 min, which is 6 times higher than that obtained on the pristine CBO/CuO photocathode. The theoretical calculations suggested that the introduction of Gd could adjust the electronic structure of CBO surface and promote 2e ORR pathway for selective production of H2O2. Our work not only provides a new strategy for designing highly efficient photocathode for H2O2 production but also will evoke more interest in photoelectrocatalytic ORR through inorganic semiconductor photocathode.

Catalytic combustion is an efficient and economical technique to deal with the air pollution of diluted volatile organic compounds (VOCs). In this work, oxygen-rich CeO2-Nb2O5 mixed oxides (CexNb1-xO4+δ) with varied Ce/Nb molar ratios in the bulk synthesized by modified sol–gel method were investigated for complete catalytic combustion of VOCs as exemplified by monochlorobenzene and toluene. To reveal the structure–function relationship of these materials, comprehensive catalytic performance evaluation and characterizations were performed, which showed that the 4Ce1Nb catalyst (CeO2-Nb2O5 with Ce/Nb molar ratio of 4:1) displayed superb apparent catalytic activity. Complete oxidation could be accomplished below 300 °C, which was significantly lower than that of single-component CeO2 or Nb2O5, as well as some other types of V and Cr based mixed oxide catalysts. Moreover, the apparent catalytic activity of 4Ce1Nb could be maintained for at least 100 h at 280 °C with high selectivity to the formation of HCl and CO2. The improved catalytic performance of 4Ce1Nb could be ascribed to the formation of oxygen-rich CexNb1-xO4+δ mixed oxides with high dispersion of Ce and Nb species into each other, the strong interaction of Ce–O-Nb, an abundance of active oxygen species, high specific surface area and mesoporous structure.

A facile and eco-friendly protocol for the synthesis of sulfonylhydrazones from sulfonyl chlorides, hydrazine hydrate and vinyl azides was developed. The unique advantage of this approach is that desired products can be obtained efficiently in water, which meets the requirements of green chemistry and provides good perspectives for the sustainable production of new drug candidate. Also, this reaction proceeded in moderate to good yields with a wide tolerance of functional groups.

Electrocatalysts are vulnerable to be influenced during the oxygen reduction reaction (ORR) process on the cathodes of direct methanol fuel cells, mainly by the reaction products and air-containing traces of acidic gas carbon dioxide (CO₂), leading to low activity and durability. Herein, an ORR catalyst was derived from furfural, nitrogen carbide (g-C₃N₄), and calcium chloride (CaCl₂) via a dual-template method, resulting in two-dimensional graphene-like carbon nanosheets with a micro–mesoporous architecture, large Brunauer–Emmett–Teller surface areas (748 m²/g), an ultrahigh pyridinic nitrogen-doping level (13.6 wt %), and high degree of graphitization. The as-synthesized sample shows high ORR performance and robust durability in both alkaline and acidic electrolytes undergoing a gas mixture of O₂ and CO₂ (95:5), demonstrating a strong tolerance of CO₂ during the ORR process. Besides, the as-prepared material also exhibits competitive properties in the selective capture of CO₂ gas versus N₂. Thus, this work provides a facile route of preparing high-performance bifunctional carbonaceous materials in both ORR and CO₂ gas capture.

A nontoxic multicarboxylic acid (critic acid) was incorporated into the chitosan/poly(ethylene oxide) composite nanofibers by electrospinning. Critic acid was used to crosslink the chitosan molecules inside the composite nanofibers at elevated temperature, which were characterized by FT-IR and XPS analyses. By increasing the critic acid loading and annealing temperature, the solvent resistance and mechanical properties of these composite nanofibers could be significantly improved. Aspirin, a model drug, has been incorporated into the composite nanofibers and the corresponding drug release performances in PBS solution were evaluated. With the increasing of annealing temperature, the drug release rate of the composite nanofibers was decreasing, which could be ascribed to the reduced swelling ratio and concentration of free volume holes in composite nanofibers. Moreover, the cumulative released aspirin amount in certain release time could be finely tuned by adjusting the initial aspirin loading in the composite nanofibers.

The exploration of Pickering emulsions is very significant owing to their versatile and important applications in many scopes. In this study, synthesis of a novel kind of single-chain polymer nanoparticle (SCPN) and its stabilized Pickering emulsions were demonstrated. To this end, linear-dendritic diblock copolymers consisting of poly((2-dimethylamino) ethyl methacrylate) (PDMAEMA) blocks and four-generation dendritic aliphatic polyester blocks (G

Biopolymer of chitosan (CS) and titanium pillared clays (Ti-PILCs) have been combined in a hybrid as advanced supports for immobilization of PdOx=0,1 species to prepare novel PdOx=0,1@Ti-PILC/CS nano-composite catalysts. The Ti-PILC materials showed high specific surface areas and abundant meso-porous structure with many irregular pore channels caused by collapses of layered structure of clay during Ti pillaring process. Both CS chains and sub-nano sized PdOx particles were successfully incorporated into the pore channels of Ti-PILC, resulting in a decrease in both the specific surface areas and uniform distribution of pore size. Besides conventional methods characterizations, the strong interactions between PdOx species and Ti-PILC/CS support were further evidenced with positron annihilation lifetime spectroscopy studies. The resultant PdOx@Ti-PILC/CS catalyst was highly active for the coupling reactions of aryl halides with phenyl acetylenes. It was recyclable and gave excellent yield up to 13 runs with low leaching of Pd species.

A flexible and efficient three-component reaction has been established for the synthesis of bioactive 1,6-naphthyridine-2,5-diones by using low-cost and readily accessible aminopyridinones, aromatic aldehydes, and Meldrum’s acid as starting materials. The main advantage of this synthetic method is that the yields of the resulting 1,6-naphthyridine-2,5-dione derivatives under ultrasound irradiation in water with acetic acid as catalyst are higher than those from the classical-heating method. The probable reaction mechanism indicates that the process involves a Knoevenagel condensation, Michael addition, and cyclization sequence.

An efficient and eco-friendly approach for highly diastereoselective synthesis of spirocycloalkane fused pyrazolo[3,4-b]pyridine derivatives has been developed. The one-pot three-component reaction enables multiple bond-forming events including C–C and C–N bonds under mild conditions using easily available starting materials, leading to diastereoselective generation of N-containing spirocycles. The advantages of inexpensive and easily available starting materials, green and mild reaction conditions, recyclable and easily separable heterogeneous catalysts, broad substrate scope and simple one-pot operation make this strategy highly attractive.

Atomically dispersed M-N-C has been considered an effective catalyst for various electrochemical reactions such as oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which faces the challenge of increasing metal load while simultaneously maintaining catalytic performance. Herein, we put forward a strategy for boosting catalytic performances of a single Cu atom coordinated with three N atoms (CuN

A facile and efficient oxidative functionalization of vinyl azides with aldehydes furnishing a diverse array of β-acylated enaminones was developed. The cross coupling was accomplished in the presence of CuCl

An environmentally benign, cost-efficient and practical methodology for the room temperature synthesis of 2-arylacetophenones in water has been discovered. The facile and efficient transformation involves the oxidative radical addition of arylhydrazines with α-aryl vinyl azides in the presence of H

Lithium-sulfur battery is one of the most promising applicants for the next generation of energy storage devices whose commercial applications are impeded by the key issue of the shuttle effect. To overcome this obstacle, various two-dimensional (2D) carbon-based metal-free compounds have been proposed to serve as anchoring materials for immobilizing soluble lithium polysulfides (LiPs), which however suffer from low electronic conductivity implying unsatisfactory performance for catalyzing sulfur redox. Therefore, we have predicted metallic C

Responsive Pickering emulsions exhibit promising application in industry owing to the integration of the high storage stability with on-demand demulsification. In this study, stimuli-responsive Pickering emulsions stabilized by poly[oligo(ethylene glycol) methyl ether methacrylate]

Two-dimensional SnS

A concise total synthesis of (±)-conolidine, a potent nonopioid analgesic, in 19% overall yield is described here. A gold(I)-catalyzed Conia-ene reaction (Toste cyclization) and a Pictet-Spengler reaction served as key transformations for assembling the 1-azabicyclo[4.2.2]decane core and defining the geometry of the exocyclic double bond. The activation energies of formation of the vinyl-gold intermediates were calculated and revealed a silyl enol ether with an unprotected indole moiety as a suitable precursor for the Toste cyclization. This six-step synthesis did not involve any nonstrategic redox manipulations.

The mesoporous phenol-formaldehyde resins (PFR) were synthesized using formaldehyde, phenol, F127 template as raw materials by high temperature hydrothermal method under different temperatures. Nitrogen doped mesoporous PFR were synthesized in the same way with another additional raw material HMTA. Two series of carbon materials PCs and PCNs were obtained after calcinating PFR at 700, 800, 900 °C. N2 adsorption analysis indicates that both the two kind of carbon materials have relatively large specific surface area (325–619 cm2/g for PCs and 431–580 cm2/g for PCNs). TEM and XRD analyses prove highly ordered mesoporous structure of the samples. Both the elemental analysis and IR results suggest a high carbon content and the abundant fused-ring structure of the test materials. The positron annihilation spectra show that the corresponding intensity I3 of the longest lifetime component τ3 is less than 2%, indicating that the π electrons in the fused rings with low ionization energy are capable of trapping positrons and inhibiting the formation of o-Ps.

Colloidosomes have gained intensive attention in the past years due to their substantial applications in wide scopes involving encapsulation, catalysis, and drug delivery, etc. In this study, we depicted the templated fabrication of well-shaped colloidosomes with tunable shell thickness by Pickering emulsion at a mild condition. To this end, toluene-in-water Pickering emulsion stabilized by cetyltrimethylammonium bromide (CTAB)–modified polydopamine (PDA) nanoparticles (PDA@CTAB) was prepared. After the covalent cross-linking of PDA nanoparticles assembled on the surface of an oil droplet through chemical reactions occurring in toluene phase, exclusive intra-colloidosomes were afforded. The shell thickness of colloidsomes could be roughly tuned by the adjustment of the amount of the reactive monomers in the oil phase. Our investigations revealed that CTAB was critical for the successful fabrication of well-shaped colloidosomes. Otherwise, only irregular structures were obtained if pristine PDA–stabilized Pickering emulsion was applied. The current strategy could enable hydrophobic cargo, such as 10-hydroxycamptothecin to be encapsulated while colloidosomes were created. The release behavior of the encapsulated cargoes was also investigated.

Injectable self-healable nanocomposite (NC) hydrogels with good mechanical strength and mussel-inspired adhesive property were described in this study. Such NC hydrogels were constructed with a sim...