Bilayer electrified-membrane with pair-atom tin catalysts for near-complete conversion of low concentration nitrate to dinitrogen.

Discharge of wastewater containing nitrate (NO) disrupts aquatic ecosystems even at low concentrations. However, selective and rapid reduction of NO at low concentration to dinitrogen (N) is technically challenging. Here, we present an electrified membrane (EM) loaded with Sn pair-atom catalysts for highly efficient NO reduction to N in a single-pass electrofiltration.

Insights into the Roles of Different Iron Species on Zeolites for NO Selective Catalytic Reduction by CO.

Iron zeolites are promising candidates for mitigating nitrous oxide (NO), a potent greenhouse gas and contributor to stratospheric ozone destruction. However, the atomic-level mechanisms by which different iron species, including isolated sites, clusters, and particles, participate in NO decomposition in the presence of CO still remain poorly understood, which hinders the application of the reaction in practical technology. Herein, through experiments and density functional theory (DFT) calculations, we identified that isolated iron sites were active for NO activation to generate adsorbed O* species, which readily reacted with CO following the Eley-Rideal (E-R) mechanism.

Solution Processable Metal-Organic Frameworks: Synthesis Strategy and Applications.

Metal-organic frameworks (MOFs), constructed by inorganic secondary building units with organic linkers via reticular chemistry, inherently suffer from poor solution processability due to their insoluble nature, resulting from their extensive crystalline networks and structural rigidity. The ubiquitous occurrence of precipitation and agglomeration of MOFs upon formation poses a significant obstacle to the scale-up production of MOF-based monolith, aerogels, membranes, and electronic devices, thus restricting their practical applications in various scenarios. To address the previously mentioned challenge, significant strides have been achieved over the past decade in the development of various strategies aimed at preparing solution-processable MOF systems.

Construction of Solution Processable NUS-8/PANI Nanosheets via Template-Directed Polymerization for Ultratrace Gas Sensing.

The advancement of wireless gas sensing signifies a substantial leap forward in gas detection and intelligent monitoring technologies. This necessitates stringent design criteria for gas sensitive materials with good solution processability, conductivity, and porosity, whose design and synthesis remain challenging yet highly sought-after. Herein, the fabrication of NUS-8/polyaniline (PANI) nanosheets is presented with excellent solution processability, high porosity, triboelectric property, and superior electrical conductivity via a template-directed polymerization strategy.

Progress and challenges in nitrous oxide decomposition and valorization.

Nitrous oxide (NO) decomposition is increasingly acknowledged as a viable strategy for mitigating greenhouse gas emissions and addressing ozone depletion, aligning significantly with the UN's sustainable development goals (SDGs) and carbon neutrality objectives. To enhance efficiency in treatment and explore potential valorization, recent developments have introduced novel NO reduction catalysts and pathways. Despite these advancements, a comprehensive and comparative review is absent.

Effects of Ionic Interferents on Electrocatalytic Nitrate Reduction: Mechanistic Insight.

Nitrate, a prevalent water pollutant, poses substantial public health concerns and environmental risks. Electrochemical reduction of nitrate (eNORR) has emerged as an effective alternative to conventional biological treatments. While extensive lab work has focused on designing efficient electrocatalysts, implementation of eNORR in practical wastewater settings requires careful consideration of the effects of various constituents in real wastewater.

High-Efficiency Electrocatalytic Reduction of NO with Single-Atom Cu Supported on Nitrogen-Doped Carbon.

Nitrous oxide (NO) is a potent greenhouse gas with a high global warming potential, emphasizing the critical need to develop efficient elimination methods. Electrocatalytic NO reduction reaction (NORR) stands out as a promising approach, offering room temperature conversion of NO to N without the production of NO byproducts. In this study, we present the synthesis of a copper-based single-atom catalyst featuring atomic Cu on nitrogen-doped carbon black (Cu-NCB).

Electrochemical Reduction of Flue Gas Denitrification Wastewater to Ammonia Using a Dual-Defective CuO@Cu Heterojunction Electrode.

Wet flue gas denitrification offers a new route to convert industrial nitrogen oxides (NO) into highly concentrated nitrate wastewater, from which the nitrogen resource can be recovered to ammonia (NH) via electrochemical nitrate reduction reactions (NITRRs). Low-cost, scalable, and efficient cathodic materials need to be developed to enhance the NH production rate. Here, electrodeposition was adopted to fabricate a foamy Cu-based heterojunction electrode containing both Cu-defects and oxygen vacancy loaded CuO (OVs-CuO), which achieved an NH yield rate of 3.

Peroxymonosulfate-Based Electrochemical Advanced Oxidation: Complication by Oxygen Reduction Reaction.

Peroxymonosulfate (PMS)-based electrochemical advanced oxidation processes (EAOPs) have received widespread attention in recent years, but the precise nature of PMS activation and its impact on the overall process performance remain poorly understood. This study presents the first demonstration of the critical role played by the oxygen reduction reaction in the effective utilization of PMS and the subsequent enhancement of overall pollutant remediation. We observed the concurrent generation of HO via oxygen reduction during the cathodic PMS activation by a model nitrogen-doped carbon nanotube catalyst.

Research status of facial nerve repair.

The facial nerve, also known as the seventh cranial nerve, is critical in controlling the movement of the facial muscles. It is responsible for all facial expressions, such as smiling, frowning, and moving the eyebrows. However, damage to this nerve can occur for a variety of reasons, including maxillofacial surgery, trauma, tumors, and infections.

Highly Selective Nitrite Hydrogenation to Ammonia over Iridium Nanoclusters: Competitive Adsorption Mechanism.

Wet denitrification is a promising approach to control nitrogen oxides (NO) produced in fossil fuel combustion. Yet, the highly concentrated nitrite (NO) wastewater generated poses a major threat to the aqueous environment. Here, iridium nanoclusters ( = 1.

Metal-Organic Framework Coated Devices for Gas Sensing.

The demand for monitoring chemical and physical information surrounding, air quality, and disease diagnosis has propelled the development of devices for gas sensing that are capable of translating external stimuli into detectable signals. Metal-organic frameworks (MOFs), possessing particular physiochemical properties with designability in topology, specific surface area, pore size and/or geometry, potential functionalization, and host-guest interactions, reveal excellent development promises for manufacturing a variety of MOF-coated sensing devices for multitudinous applications including gas sensing. The past years have witnessed tremendous progress on the preparation of MOF-coated gas sensors with superior sensing performance, especially high sensitivity and selectivity.

Contrasting Capability of Single Atom Palladium for Thermocatalytic versus Electrocatalytic Nitrate Reduction Reaction.

The occurrence of high concentrations of nitrate in various water resources is a significant environmental and human health threat, demanding effective removal technologies. Single atom alloys (SAAs) have emerged as a promising bimetallic material architecture in various thermocatalytic and electrocatalytic schemes including nitrate reduction reaction (NRR). This study suggests that there exists a stark contrast between thermocatalytic (T-NRR) and electrocatalytic (E-NRR) pathways that resulted in dramatic differences in SAA performances.

Adsorption characteristics of dichloromethane-ethyl acetate/toluene vapor on a hypercrosslinked polystyrene adsorbent.

Dichloromethane (DCM), a typical representative of chlorinated volatile organic compounds (CVOCs), is usually exhausted along with other volatile organic compounds (VOCs), such as toluene and ethyl acetate, in industrial factories. To address the complexity of the components, the large variation in concentration of each component and the water content of the exhaust gases emitted from the pharmaceutical and chemical industries, the adsorption characteristics of DCM, toluene (MB), and ethyl acetate (EAC) vapors on hypercrosslinked polymeric resins (NDA-88) were studied by dynamic adsorption experiments. Furthermore, the adsorption characteristics of NDA-88 for binary vapor systems of DCM-MB and DCM-EAC at different concentration ratios and the nature of the interaction force with the three VOCs were explored.

Single-Atom Catalysts in Environmental Engineering: Progress, Outlook and Challenges.

Recently, single-atom catalysts (SACs) have attracted wide attention in the field of environmental engineering. Compared with their nanoparticle counterparts, SACs possess high atomic efficiency, unique catalytic activity, and selectivity. This review summarizes recent studies on the environmental remediation applications of SACs in (1) gaseous: volatile organic compounds (VOCs) treatment, NO reduction, CO reduction, and CO oxidation; (2) aqueous: Fenton-like advanced oxidation processes (AOPs), hydrodehalogenation, and nitrate/nitrite reduction.

Free-standing membrane incorporating single-atom catalysts for ultrafast electroreduction of low-concentration nitrate.

The release of wastewaters containing relatively low levels of nitrate (NO) results in sufficient contamination to induce harmful algal blooms and to elevate drinking water NO concentrations to potentially hazardous levels. In particular, the facile triggering of algal blooms by ultra-low concentrations of NO necessitates the development of efficient methods for NO destruction. However, promising electrochemical methods suffer from weak mass transport under low reactant concentrations, resulting in long treatment times (on the order of hours) for complete NO destruction.

Enhancing the activity of Pd ensembles on graphene by manipulating coordination environment.

Atomic dispersion of metal catalysts on a substrate accounts for the increased atomic efficiency of single-atom catalysts (SACs) in various catalytic schemes compared to the nanoparticle counterparts. However, lacking neighboring metal sites has been shown to deteriorate the catalytic performance of SACs in a few industrially important reactions, such as dehalogenation, CO oxidation, and hydrogenation. Metal ensemble catalysts (M), an extended concept to SACs, have emerged as a promising alternative to overcome such limitation.

Importance of structural hinderance in performance-stability equilibrium of organic photovoltaics.

Power conversion efficiency and long-term stability are two critical metrics for evaluating the commercial potential of organic photovoltaics. Although the field has witnessed a rapid progress of efficiency towards 19%, the intrinsic trade-off between efficiency and stability is still a challenging issue for bulk-heterojunction cells due to the very delicate crystallization dynamics of organic species. Herein, we developed a class of non-fullerene acceptors with varied side groups as an alternative to aliphatic chains.

Classical and Nonclassical Nucleation and Growth Mechanisms for Nanoparticle Formation.

All solid materials are created via nucleation. In this evolutionary process, nuclei form in solution or at interfaces, expand by monomeric growth and oriented attachment, and undergo phase transformation. Nucleation determines the location and size of nuclei, whereas growth controls the size, shape, and aggregation of newly formed nanoparticles.

Single-Atom Cobalt Incorporated in a 2D Graphene Oxide Membrane for Catalytic Pollutant Degradation.

We introduce a new graphene oxide (GO)-based membrane architecture that hosts cobalt catalysts within its nanoscale pore walls. Such an architecture would not be possible with catalysts in nanoscale, the current benchmark, since they would block the pores or alter the pore structure. Therefore, we developed a new synthesis procedure to load cobalt in an atomically dispersed fashion, the theoretical limit in material downsizing.

A Protocol for Electrocatalyst Stability Evaluation: HO Electrosynthesis for Industrial Wastewater Treatment.

Electrocatalysis has been proposed as a versatile technology for wastewater treatment and reuse. While enormous attention has been centered on material synthesis and design, the practicality of such catalyst materials remains clouded by a lack of both stability assessment protocols and understanding of deactivation mechanisms. In this study, we develop a protocol to identify the wastewater constituents most detrimental to electrocatalyst performance in a timely manner and elucidate the underlying phenomena behind these losses.

Elucidating the Role of Single-Atom Pd for Electrocatalytic Hydrodechlorination.

In this study, we loaded Pd catalysts onto a reduced graphene oxide (rGO) support in an atomically dispersed fashion [i.e., Pd single-atom catalysts (SACs) on rGO or Pd/rGO] via a facile and scalable synthesis based on anchor-site and photoreduction techniques.

Bacterial Distribution, Biogenic Amine Contents, and Functionalities of Traditionally Made Doenjang, a Long-Term Fermented Soybean Food, from Different Areas of Korea.

Since doenjang quality depends on the bacterial composition, which ambient bacteria in the environment and production conditions influence, a complete understanding of the bacteria community in traditionally madetraditionally made doenjang (TMD) from different regions is needed. We aimed to investigate the bacteria composition and quality of TMD in the following areas: Chonbuk (CB), Chonnam (CN), Kyungsang (KS), Kangwon (KW), Chungchung (CC) provinces, and Jeju island (JJ) of Korea. Twenty-nine TMD samples from different regions were used to assess biogenic amine contents, bacteria composition using next-generation methods, and metabolic functions of the bacteria using Picrust2.

Quantitative changes of Veillonella, Streptococcus, and Neisseria in the oral cavity of patients with recurrent aphthous stomatitis: A systematic review and meta-analysis.

Objective: This study aimed to investigate that these bacteria counts in the oral cavity were modulated by the recurrent aphthous stomatitis (RAS) status according to age and ethnicity with a systematic review and meta-analysis.

Design: The relevant case-control studies were searched in the literature database in English, Korean, and Chinese until June 2020 using keywords, and the literature was screened and collated for Review Manager analysis. Sensitivity analysis and quality check of the included literature were conducted.