BiOCO/BiOS S-scheme n-n heterojunction with boosted photocatalytic degradation for bisphenol A.

Bisphenol A (BPA) is considered to be a typical endocrine-disrupting compounds (EDCs), and its widespread existence in nature is quite harmful to human and ecological environment. The S-scheme n-n heterojunction composite (BiOCO/BiOS) was constructed via a facile two-step chemical precipitation method for the removal of BPA in water environment. The optimal composite catalyst exhibited outstanding catalytic activity for BPA, obtaining approximately 0.

Unravelling the Photoelectrochemical Water Splitting of Nanometer-Thick Carbon Nitride Layer.

Matching the thickness of the graphitic carbon nitride (CN) nanolayer with the charge diffusion length is expected to compensate for the poor intrinsic conductivity and charge recombination in CN for photoelectrochemical cells (PEC). Herein, the compact CN nanolayer with tunable thickness is in situ coated on carbon fibers. The compact packing along with good contact with the substrate improves the electron transport and alleviates the charge recombination.

Exclusive Coordination between Melem and Silver(I) Ions: From Irregular Aggregates to Nanofibers to Crystal Cubes.

There is growing focus on metal-free molecules and polymers owing to their potential applications in various energy and catalysis-related applications. Melem (2,5,8-triamino--heptazine, CHN) has emerged as a metal-free material for solar-to-fuel conversion. However, its reactivity with metal ions or organic molecules has never been reported although it possesses multiple supramolecular interaction sites.

Progress on quantum dot photocatalysts for biomass valorization.

Biomass with abundant reproducible carbon resource holds great promise as an intriguing substitute for fossil fuels in the manufacture of high-value-added chemicals and fuels. Photocatalytic biomass valorization using inexhaustible solar energy enables to accurately break desired chemical bonds or selectively functionalize particular groups, thus emerging as an extremely creative and low carbon cost strategy for relieving the dilemma of the global energy. Quantum dots (QDs) are an outstandingly dynamic class of semiconductor photocatalysts because of their unique properties, which have achieved significant successes in various photocatalytic applications including biomass valorization.

Photocatalytic H O Generation Reaction with a Benchmark Rate at Air-Liquid-Solid Joint Interfaces.

The rapid charge recombination, low selectivity for two-electron oxygen reduction reaction (ORR), and limited O diffusion rate hinder the practical applications of photocatalytic H O generation. Herein, a triphase photocatalytic system in which the H O generation occurs at the air-liquid-solid joint interfaces is developed, using polymeric carbon nitride (PCN). The introduction of pyrrole units and cyano group into PCN can promote the activation of oxygen molecules and facilitate the spatial separation of HOMO and LUMO orbits, hence improving the charge carrier separation efficiency and enhancing the formation of H O .

Large-Scale Silver Sulfide Nanomesh Membranes with Ultrahigh Flexibility.

The growth of flexible semiconductor thin films and membranes is highly desirable for the fabrication of next-generation wearable devices. In this work, we have developed a one-step, surface tension-driven method for facile and scalable growth of silver sulfide (AgS) membranes with a nanomesh structure. The nanomesh membrane can in principle reach infinite size but only limited by the reactor size, while the thickness is self-limited to ca.

A green synthesis approach toward large-scale production of benzalacetone Claisen-Schmidt condensation.

Claisen-Schmidt (CS) condensation between acetone and benzaldehyde with NaOH as the catalyst is a well-recognized pathway for the synthesis of benzalacetone (BA). However, this process is compromised by a side reaction, , a second CS reaction between benzaldehyde and the BA product. In this work, we designed a stirring-induced emulsion synthesis technique for the cyclic and scaling-up production of BA with 99 ± 1% selectivity, without the use of surfactants.

Competition of Hydrogen Bonds and Coordinate Bonds Induces a Reversible Crystal Transformation.

Achieving reversible molecular crystal transformation between coordinate aggregates and hydrogen bonded assemblies has been a challenging task because coordinate bonds are generally much stronger than hydrogen bonds. Recently, we have reported the incorporation of silver ions into the cyanuric acid-melamine (CAM) network, resulting in the formation of a 1D coordination polymer (crystal ) through forming the κN-Ag-κN coordination bonds. In this work, we find crystal will undergo reversible transformation to hydrogen bonded coordinate units (crystal ) through the breaking of coordinate chains and then the addition of CAM hydrogen bonding motifs into the framework.

Template-free construction of hollow mesoporous carbon spheres from a covalent triazine framework for enhanced oxygen electroreduction.

The construction of hollow mesoporous carbon nanospheres (HMCS) avoiding the use of traditional soft/hard templates is highly desired for nanoscience yet challenging. Herein, we report a simple and straightforward template-free strategy for preparing nitrogen, sulfur dual-doped HMCSs (N/S-HMCSs) as oxygen reduction reaction (ORR) electrocatalysts. The unique hollow spherical and mesoporous structure was in-situ formed via a thermally initiated hollowing pathway from an elaborately engineered covalent triazine framework.

Unconventional, Gram-Scale Synthesis of a Molecular Dimer Organic Luminogen with Aggregation-Induced Emission.

Organic luminogens have been widely used in optoelectronic devices, bioimaging, and sensing. Conventionally, the synthesis of organic luminogens requires sophisticated, multistep design, reaction, and isolation procedures. Herein, the products of the melt-phase condensation of benzoguanamine (BG; 2,4-diamino-6-phenyl-1,3,5-triazine) at 370-410 °C display interesting reaction-condition-dependent luminescence properties, including photoluminescence (PL) at a variety of wavelengths in the visible spectrum and quantum efficiencies (PLQE) of up to 58% in the powder form.

Dense Hydrogen-Bonding Network Boosts Ionic Conductive Hydrogels with Extremely High Toughness, Rapid Self-Recovery, and Autonomous Adhesion for Human-Motion Detection.

The construction of ionic conductive hydrogels with high transparency, excellent mechanical robustness, high toughness, and rapid self-recovery is highly desired yet challenging. Herein, a hydrogen-bonding network densification strategy is presented for preparing a highly stretchable and transparent poly(ionic liquid) hydrogel (PAM-r-MVIC) from the perspective of random copolymerization of 1-methyl-3-(4-vinylbenzyl) imidazolium chloride and acrylamide in water. Ascribing to the formation of a dense hydrogen-bonding network, the resultant PAM-r-MVIC exhibited an intrinsically high stretchability (>1000%) and compressibility (90%), fast self-recovery with high toughness (2950 kJ m), and excellent fatigue resistance with no deviation for 100 cycles.

Ultrasound-Triggered Assembly of Covalent Triazine Framework for Synthesizing Heteroatom-Doped Carbon Nanoflowers Boosting Metal-Free Bifunctional Electrocatalysis.

The construction of multiple heteroatom-doped porous carbon with unique nanoarchitectures and abundant heteroatom active sites is promising for reversible oxygen-involving electrocatalysis. However, most of the synthetic methods required the use of templates to construct precisely designed nanostructured carbon. Herein, we introduced an ultrasound-triggered route for the synthesis of a piperazine-containing covalent triazine framework (P-CTF).

Superelastic, Fatigue-Resistant, and Flame-Retardant Spongy Conductor for Human Motion Detection against a Harsh High-Temperature Condition.

The construction of wearable piezoresistive sensors with high elasticity, large gauge factor, and excellent durability in a harsh high-temperature environment is highly desired yet challenging. Here, a lightweight, superelastic, and fatigue-resistant spongy conductor was fabricated via a sponge-constrained network assembly, during which highly conductive graphene and flame-retardant montmorillonite were alternatively deposited on a three-dimensional melamine scaffold. The as-obtained spongy conductor exhibited a highly deformation-tolerant conductivity up to 80% strain and excellent fatigue resistance of 10,000 compressive cycles at 70% strain.

Graphitic Carbon Nitride Films: Emerging Paradigm for Versatile Applications.

Graphitic carbon nitride (g-CN) is a well-known two-dimensional conjugated polymer semiconductor that has been broadly applied in photocatalysis-related fields. However, further developments of g-CN, especially in device applications, have been constrained by the inherent limitations of its insoluble nature and particulate properties. Recent breakthroughs in fabrication methods of g-CN films have led to innovative and inspiring applications in many fields.

One-Minute Synthesis of a Supramolecular Hydrogel from Suspension-Gel Transition and the Derived Crystalline, Elastic, and Photoactive Aerogels.

Solutions or sols are commonly employed as the starting materials for the preparation of supramolecular hydrogels; however, suspension-based synthesis has been much less reported because of inhomogeneity and quick sedimentation of large particles in a suspension. Further, it remains a technical challenge to derive supramolecular aerogels directly from the parental hydrogels owing to the ease of structural collapse during water removal. Herein, we report a suspension-gel transition for the ultrafast synthesis of a new supramolecular hydrogel simply by adding AgNO into the aqueous suspension of cyanuric acid-melamine (CAM) aggregates.

Metal-Free Multi-Heteroatom-Doped Carbon Bifunctional Electrocatalysts Derived from a Covalent Triazine Polymer.

The construction of multi-heteroatom-doped metal-free carbon with a reversibly oxygen-involving electrocatalytic performance is highly desirable for rechargeable metal-air batteries. However, the conventional approach for doping heteroatoms into the carbon matrix remains a huge challenge owing to multistep postdoping procedures. Here, a self-templated carbonization strategy to prepare a nitrogen, phosphorus, and fluorine tri-doped carbon nanosphere (NPF-CNS) is developed, during which a heteroatom-enriched covalent triazine polymer serves as a "self-doping" precursor with C, N, P, and F elements simultaneously, avoiding the tedious and inefficient postdoping procedures.

Unique S-scheme heterojunctions in self-assembled TiO/CsPbBr hybrids for CO photoreduction.

Exploring photocatalysts to promote CO photoreduction into solar fuels is of great significance. We develop TiO/perovskite (CsPbBr) S-scheme heterojunctions synthesized by a facile electrostatic-driven self-assembling approach. Density functional theory calculation combined with experimental studies proves the electron transfer from CsPbBr quantum dots (QDs) to TiO, resulting in the construction of internal electric field (IEF) directing from CsPbBr to TiO upon hybridization.

A bioinspired microreactor with interfacial regulation for maximizing selectivity in a catalytic reaction.

We report a bioinspired emulsion microreactor composed of an electrical double layer to mimic the functions of cell membranes. This "artificial cell" can modulate the phase-oriented transport of reagents at the oil-liquid interface via the electrical double layer, affording a powerful tool to optimize the selectivity in a catalytic reaction.

Strongly interfacial-coupled 2D-2D TiO/g-CN heterostructure for enhanced visible-light induced synthesis and conversion.

Two-dimensional (2D) nanosheet-based nanocomposites have attracted intensive interest owing to the unique electronic and optical properties from their constituent phases and the synergistic effect from the heterojunctions. In this study, an interfacial coupled TiO/g-CN 2D-2D heterostructure has been prepared via in situ growth of ultrathin 2D-TiO on dispersed g-CN nanosheets. This strongly coupled 2D-2D TiO/g-CN, different from the weakly bonded 2D-TiO/g-CN heterostructures produced by mechanical mixing, has unique electronic structures and chemical states due to strong interlayer charge transfer, confirmed by both experimental and theoretical analyses.

Cryopolymerization enables anisotropic polyaniline hybrid hydrogels with superelasticity and highly deformation-tolerant electrochemical energy storage.

The development of energy storage devices that can endure large and complex deformations is central to emerging wearable electronics. Hydrogels made from conducting polymers give rise to a promising integration of high conductivity and versatility in processing. However, the emergence of conducting polymer hydrogels with a desirable network structure cannot be readily achieved using conventional polymerization methods.

Crystal Transformation from the Incorporation of Coordinate Bonds into a Hydrogen-Bonded Network Yields Robust Free-Standing Supramolecular Membranes.

In this work, we report on the synthesis of a free-standing, macroscopic robust supramolecular membrane by introducing silver-nitrogen coordinate bonding into preorganized, supramolecular hydrogen-bonded cyanuric acid-melamine (CAM) crystals. With the assistance of ammonia, silver ions competitively replace two of the three hydrogen atoms from cyanuric acid resulting in the transformation from short CAM nanorods to long CAM-Ag nanofibers (length over 1000 μm), accompanied by tautomerization of cyanuric acid. The single crystal structure of the CAM-Ag nanofibers is solved in the space group 1, with the asymmetric unit containing eight silver atoms, four melamine and four cyanuric acid molecules, which generate 1D coordination polymer chains consisting of alternating melamine and dianionic cyanurate ligands linked via silver-nitrogen bonds.

A photothermal reservoir for highly efficient solar steam generation without bulk water.

A solid photothermal reservoir is designed to implement solar-steam generation in the absence of bulk water. The photothermal reservoir is composed of a water absorbing core encapsulated by a photothermal reduced graphene oxide based aerogel sheet which absorbs light and converts it into heat thus evaporating the stored water. The photothermal reservoir is able to store 6.

Solvent-Exchange Strategy toward Aqueous Dispersible MoS Nanosheets and Their Nitrogen-Rich Carbon Sphere Nanocomposites for Efficient Lithium/Sodium Ion Storage.

Major challenges in developing 2D transition-metal disulfides (TMDs) as anode materials for lithium/sodium ion batteries (LIBs/SIBs) lie in rational design and targeted synthesis of TMD-based nanocomposite structures with precisely controlled ion and electron transport. Herein, a general and scalable solvent-exchange strategy is presented for uniform dispersion of few-layer MoS (f-MoS ) from high-boiling-point solvents (N-methyl-2-pyrrolidone (NMP), N,N-dimethyl formaldehyde (DMF), etc.) into low-boiling-point solvents (water, ethanol, etc.

Cobalt, Nitrogen-Doped Porous Carbon Nanosheet-Assembled Flowers from Metal-Coordinated Covalent Organic Polymers for Efficient Oxygen Reduction.

The breakthrough of nonprecious metal catalysts replacing platinum-based catalysts toward the oxygen reduction reaction (ORR) is extremely urgent for the development of high-efficiency energy conversation systems. Herein, a solution-processed condensation polymerization using cyanuric chloride and piperazine as the monomers was proposed for the synthesis of a nitrogen-rich covalent organic polymer (COP). High contents of precisely tailored pyridinic-N within the COP facilitate the formation of the Co/N coordination between Co ions and N species.

Palladium/Graphitic Carbon Nitride (g-C N ) Stabilized Emulsion Microreactor as a Store for Hydrogen from Ammonia Borane for Use in Alkene Hydrogenation.

Direct hydrogenation of C=C double bonds is a basic transformation in organic chemistry which is vanishing from simple practice because of the need for pressurized hydrogen. Ammonia borane (AB) has emerged as a hydrogen source through its safety and high hydrogen content. However, in conventional systems the hydrogen liberated from the high-cost AB cannot be fully utilized.