Modulating π-bridge in donor-π-acceptor covalent organic frameworks for low-energy-light-driven photocatalytic reaction.

Most of the photocatalytic reactions are currently driven by high-energy light (UV, blue light), which inevitably leads to side reactions and co-catalyst deactivation. Therefore, there is an urgent need to prepare novel photocatalysts with low-energy photocatalytic properties. Herein, we report a rational molecular design of covalent organic frameworks (COFs) equipped with donor-π-acceptor systems with different π-bridges (aromatic ring, mono- and bis-alkynyl).

Efficient unsymmetric disulfide formation by molecular-scale tailoring of ortho-polyquinone-based polymer photocatalyst.

Disulfide bonds, especially unsymmetric disulfide bonds, have important applications in bioactivity and drug molecules, but the synthesis of unsymmetric disulfide bonds remains challenging due to efficiency and selectivity issues. Herein, this work utilizes anthraquinone (AQ) and cyclictriphosphonononitrile through a nucleophilic substitution reaction to synthesize an organic polymer (ANTH-AMI) that incorporates an ortho-polyquinone (o-polyquinone) redox center. The anthraquinone molecule functions as a redox center, capable of accepting photoinduced electrons and subsequently transferring them to initiate an electron-coupled hydrogenation reaction (AQ to AQH).

Tracing groundwater nitrate sources in an intensive agricultural region integrated of a self-organizing map and end-member mixing model tool.

The traceability of groundwater nitrate pollution is crucial for controlling and managing polluted groundwater. This study integrates hydrochemistry, nitrate isotope (δN-NO and δO-NO), and self-organizing map (SOM) and end-member mixing (EMMTE) models to identify the sources and quantify the contributions of nitrate pollution to groundwater in an intensive agricultural region in the Sha River Basin in southwestern Henan Province. The results indicate that the NO-N concentration in 74% (n = 39) of the groundwater samples exceeded the WHO standard of 10 mg/L.

[Research progress on nitrate isotope coupled multi-tracer tracing groundwater nitrate pollution].

Nitrate pollution in groundwater has become a global concern. One of the most important issues in controlling the nitrate pollution of groundwater is to identify the pollution source quickly and accurately. In this review, we firstly summarized the isotopic background values of potential sources of nitrate pollution in groundwater in 17 provinces (cities, autonomous regions) and 29 study areas in China, which could provide the fundamental database for subsequent research.

Photoselectively modulating main products by changing the wavelength of visible light over D-π-A-D conjugated polymers.

The diversity of catalytic products determines the difficulty of selective product modulation, which usually relies on adjusting the catalyst and reaction conditions to obtain different main products selectively. Herein, we synthesized D-π-A-D conjugated organic polymers (TH-COP) using cyclotriphosphonitrile, alkyne, 2H-benzimidazole, and sulfur units as electron donors, π bridges, electron acceptors, and electron donors, respectively. TH-COP exhibited excellent photoinduced carrier separation and redox ability under different visible light wavelengths, and the main products of its CO reduction are CH (1000.

Effect of in situ ultrasonic wave and influent ammonia nitrogen fluctuation on stability of aerobic granular sludge.

This study elucidates the impact of fluctuating influent conditions and in situ ultrasonic wave exposure on the stability of aerobic granular sludge (AGS) in the treatment of simulated wastewater emanating from rare earth mining operations. During a stable influent period spanning from Day 1 to Day 95, the seed granules underwent an initial disintegration followed by a re-granulation phase. The secondary granulation was achieved on Day 80 and Day 40 for the ultrasonic reactor (R1) and the control reactor (R2), respectively.

Converting commercial BiO particles into BiOSe@BiOSe nanosheets for "rocking chair" zinc-ion batteries.

The development of a low-cost, high-capacity, and insertion-type anode is key for promoting "rocking chair" zinc-ion batteries. Herein, commercial BiO (BiO) particles are transformed into BiOSe@BiOSe (BiOSe) nanosheets through a simple selenylation process. The change in morphology from commercial BiO particle to BiOSe nanosheet leads to an increased specific surface area of the material.

Stability of aerobic granular sludge for treating inorganic wastewater with different nitrogen loading rates.

This paper investigated the effect of nitrogen loading rates (NLRs) on the stability of aerobic granular sludge (AGS) for treating simulated ionic rare earth mine wastewater with high ammonia nitrogen and extremely low organic content. Mature AGS from a sequencing batch reactor (SBR) was seeded into five identical SBRs (R1, R2, R3, R4 and R5). The five reactors were operated with different NLRs (0.

Ni-doped BiOCO nanosheet with H/Zn co-insertion for "rocking chair" zinc-ion battery.

Developing insertion-type anode is key to advancing "rocking chair" zinc-ion batteries, though there are few reported insertion-type anodes. Herein, the BiOCO is a high-potential anode, with a special layered structure. A one-step hydrothermal method was used to prepare Ni-doped BiOCO nanosheet, and also a free-standing electrode consisting of Ni-BiOCO and CNTs was designed.

BiOIO@Zn(PO)·4HO Heterojunction with Fast Ionic Diffusion Kinetics for Long-Life "Rocking-Chair" Zinc Ion Batteries.

Increasing insertion host materials are developed as high-performance anodes of "rocking-chair" zinc ion batteries. However, most of them show unsatisfactory rate capabilities. Herein, layered BiOIO is reported as an excellent insertion host and a zinc ion conductor, i.

Construction of dual active sites on the CuAg plasmonic aerogel for simultaneously efficient photocatalytic CO2 reduction and H2 production.

Photocatalytic CO reduction and H production are a competitive reaction, and existing active sites cannot take into account the simultaneous gas-solid and liquid-solid reaction processes. Hence, a metallic aerogel (CuAg) with dual active sites was constructed via straightforward in-situ reduction process. CuAg aerosol has larger porosity and CO adsorption capacity, which enables HO and CO to fully contact it.

Few-Atomic-Layered Co-Doped BiOBr Nanosheet: Free-Standing Anode with Ultrahigh Mass Loading for "Rocking Chair" Zinc-Ion Battery.

Insertion host materials are considered as a candidate to replace metallic Zn anode. However, the high mass loading anode with good electrochemical performances is reported rarely. Herein, a few-atomic-layered Co-doped BiOBr nanosheet (Co-UTBiOBr) is prepared via one-step hydrothermal method and a free-standing flexible electrode consisting of Co-UTBiOBr and CNTs is designed.

Stability of aerobic granular sludge for simultaneous nitrogen and Pb(II) removal from inorganic wastewater.

In this paper, we proposed a strategy for the establishment of an aerobic granular sludge (AGS) system for simultaneous nitrogen and Pb(II) removal from inorganic wastewater. AGS was stored in lead nitrate solution to select functional bacteria resistant to lead poison, and then an AGS system for ammonia nitrogen (180-270 mg/L) and Pb(II) (15-30 mg/L) removal was established based on carbon dosing and a two-stage oxic/anoxic operational mode. After storage for 40 days, the stability of AGS decreased because specific oxygen uptake rate, nitrification rate and abundance of decreased to different degrees compared with those before storage.

BiOI Nanopaper As a High-Capacity, Long-Life and Insertion-Type Anode for a Flexible Quasi-Solid-State Zn-Ion Battery.

The development of intercalation anodes with high capacity is key to promote the progress of "rocking-chair" Zn-ion batteries (ZIBs). Here, layered BiOI is considered as a promising electrode in ZIBs due to its large interlayer distance (0.976 nm) and low Zn diffusion barrier (0.

Cultivation of autotrophic nitrifying granular sludge for simultaneous removal of ammonia nitrogen and Tl(I).

Autotrophic nitrifying granular sludge (ANGS) was cultivated for the simultaneous removal of ammonia nitrogen and Tl(I) from inorganic wastewater. The chemical oxygen demand (COD) in the influent gradually decreased to approximately zero in four parallel sequencing batch reactors (B: blank controller, B: 10 mL of added nitrifying bacteria concentrate in each cycle, B: 1 mg/L Tl(I) added in each cycle and B: 10 mL of added nitrifying bacteria concentrate and 1 mg/L Tl(I) in each cycle) within 15 days. The main properties, such as the granulation rate and specific oxygen uptake rate (SOUR) of the ANGS in B, B, B and B tended to be stable within 40, 33, 30 and 33 days, the removal efficiencies of Tl(I) were 59.

Coupling of endogenous/exogenous nitrification and denitrification in an aerobic granular sequencing batch reactor.

The performance of endogenous/exogenous nitrification and denitrification in an aerobic granular sequencing batch reactor was investigated for treating inorganic wastewater with ammonia nitrogen of 250 mg/L. The sequencing batch reactor with an effective volume of 120.5 L was started by seeding autotrophic nitrifying granular sludge (ANGS) and operated under oxic (110 min)/anoxic (120 min)/oxic (110 min) aeration mode.

[Effect of Controlling Heavy Metals in Soil of Rare Earth Mining Area by Biochar Supported Graphene Oxide].

Using navel orange peels and natural graphite as raw materials, biochar-supported graphene oxide (BGO) material was prepared using an improved hummer and co-pyrolysis method. The effects of BGO on the forms of heavy metals in the soil of a rare earth mining area were investigated via a soil passivation experiment. The soil column leaching experiment was carried out to explore the change characteristics of heavy metal content in leaching filtrate and the vertical migration law of heavy metals in soil, and the accumulation and release model of heavy metals under leaching conditions was determined.

Fast synthesis of porous iron doped CeO with oxygen vacancy for effective CO photoreduction.

The activity of photocatalytic CO conversion to carbon-containing products is determined by the adsorption and activation of CO molecules on the surface of catalyst. Here, iron doped porous CeO with oxygen vacancy (PFeCe) was prepared by one-step combustion method. The amount of CO adsorbed via using the porous structure has been significantly increased in the case of a relatively small specific surface area and CO molecules are more easily captured and undergo a reduction reaction with photoinduced carriers.

Turning commercial MnO (≥85 wt%) into high-crystallized K-doped LiMnO cathode with superior structural stability by a low-temperature molten salt method.

The obtainment of low-cost, easily prepared and high-powered LiMnO is the key to achieve its wide application in various electronic devices. In this work, a mild and easily scaled molten salt method (KCl@LiCl) is utilized to convert commercial MnO to the high-performance LiMnO. At the same reaction temperature, the molten salt method leads to the formation of K-doped LiMnO with higher crystallinity compared to the conventional solid state method, which contributes to the improved inner charge transfer.

Molten salt synthesis of KCl-preintercalated CN nanosheets with abundant pyridinic-N as a superior anode with 10 K cycles in lithium ion battery.

The graphitic carbon nitride is considered as the promising anode of lithium ion battery due to its high theoretical capacity (>1000 mAh g) and easy synthesis method. But the electrochemical inactivity and the structural collapse during cycles lead to its poor electrochemical performance in practice. Here, an interesting molten salt method is used to obtain the KCl-preintercalated carbon nitride nanosheets with abundant N vacancies and pyridinic-N.

Line defects in plasmatic hollow copper ball boost excellent photocatalytic reaction with pure water under ultra-low CO concentration.

By using a low CO concentration as a C1 source, the design of a plasmonic catalyst that can effectively photocatalytic CO reduction is of great significance for sustainable and ecological development. Herein, the space confinement effect and liquid environment of the molten salt result in uniform hollow structure, while the strong aggressive force furnished via using molten salt enhances the formation of line defects. This special structure can not only provide a large number of active sites but also greatly accelerate the transport of photoinduced charge carriers.

Controllable synthesis of porous silver cyanamide nanocrystals with tunable morphologies for selective photocatalytic CO reduction into CH.

The conversion of CO driven by solar energy into carbon-containing fuel has huge potential applications. However, most photocatalysts can only promote the two-electron reduction process to generate CO, and it is difficult to produce eight-electron CH, which is more valuable and can store more solar energy. Herein, we prepared porous silver cyanamide nanocrystals with tunable morphologies via a facile synthesis strategy.

Exploring potential impact(s) of cerium in mining wastewater on the performance of partial-nitrification process and nitrogen conversion microflora.

Cerium Ce(III) is one of the major pollutants contained in wastewater generated during Ce(III) mining. However, the effect(s) of Ce(III) on the functional genera responsible for removing nitrogen biologically from wastewater has not been studied and reported. In this study, the effects of Ce(III) on aspects of partial-nitritation-(PN) process including ammonia oxidation rate (AOR), process kinetics, and microbial activities were investigated.

Ultrathin MXene "bridge" to accelerate charge transfer in ultrathin metal-free 0D/2D black phosphorus/g-CN heterojunction toward photocatalytic hydrogen production.

The fabrication of ultrathin MXene (TiC)-based photocatalysts is highly intriguing as the charges can vectorially transfer along the two-dimensional (2D) direction despite being challenging. Herein, ultrathin TiC (TiC) nanosheets with excellent conductivity are rationally introduced to ultrathin metal-free 0D/2D black phosphorus (BQ)/ultrathin g-CN (UCN) heterojunction for improving photocatalytic H production activity. The optimized BQ/TiC/UCN composite displayed obvious advantages such as the strong interfacial contact and enhanced visible-light capture.

Rapid cultivation and stability of autotrophic nitrifying granular sludge.

Autotrophic nitrifying granular sludge (ANGS) was cultivated by gradually decreasing the influent organics and adding exogenous nitrifying bacteria. Under the strategy, ANGS was domesticated within 36 days. Stability of the seed heterotrophic granules decreased significantly during conversion of organic wastewater to inorganic ammonia wastewater.