Exploration of metal-free 2D electrocatalysts toward the oxygen electroreduction.

The advancement of economical and readily available electrocatalysts for the oxygen reduction reaction (ORR) holds paramount importance in the advancement of fuel cells and metal-air batteries. Recently, 2D non-metallic materials have obtained substantial attention as viable alternatives for ORR catalysts due to their manifold advantages, encompassing low cost, ample availability, substantial surface-to-volume ratio, high conductivity, exceptional durability, and competitive activity. The augmented ORR performances observed in metal-free 2D materials typically arise from heteroatom doping, defects, or the formation of heterostructures.

Interface Engineering via TiCT MXene Enabled Highly Efficient Bifunctional NiCoP Array Catalysts for Alkaline Water Splitting.

Developing a non-noble metal-based bifunctional electrocatalyst with high efficiency and stability for overall water splitting is desirable for renewable energy systems. We developed a novel method to fabricate a heterostructured electrocatalyst, comprising a NiCoP nanoneedle array grown on TiCT MXene-coated Ni foam (NCP-MX/NF) using a dip-coating hydrothermal method, followed by phosphorization. Due to the abundance of active sites, enhanced electronic kinetics, and sufficient electrolyte accessibility resulting from the synergistic effects of NCP and MXene, NCP-MX/NF bifunctional alkaline catalysts afford superb electrocatalytic performance, with a low overpotential (72 mV at 10 mA cm for HER and 303 mV at 50 mA cm for OER), a low Tafel slope (49.

Polymer-Covered Copper Catalysts Alter the Reaction Pathway of the Electrochemical CO Reduction Reaction.

The electrochemical CO reduction reaction (CORR) has attracted considerable attention recently due to the potential conversion of atmospheric CO into useful organic products by utilizing electricity from renewable energy sources. However, the selective formation of desired products only via CORR has been elusive due to the presence of a myriad of competing reaction pathways, thus calling for effective strategies controlling the reaction coordinates. The control of binding energies of the reaction intermediate, such as *CO, is pivotal to manipulating reaction pathways, and various attempts have been made to accomplish this goal.

Chemical Fields: Directing Atom Migration in the Multiphasic Nanocrystal.

ConspectusAtoms in a bulk solid phase are usually trapped to fixed positions and can change their position only under certain conditions (e.g., at a melting point) due to the high energy barrier of migration between positions within the crystal lattice.

Mn-Dopant Differentiating the Ru and Ir Oxidation States in Catalytic Oxides Toward Durable Oxygen Evolution Reaction in Acidic Electrolyte.

Designing an efficient and durable electrocatalyst for the sluggish oxygen evolution reaction (OER) at the anode remains the foremost challenge in developing proton exchange membrane (PEM) electrolyzers. Here, a highly active and durable cactus-like nanoparticle with an exposed heterointerface between the IrO and the low oxidation state Ru by introducing a trace amount of Mn dopant is reported. The heterostructure fabrication relies on initial mixing of the Ru and Ir phases before electrochemical oxidation to produce a conjoined Ru/IrO heterointerface.

Pd Pb Nanosponges for Selective Conversion of Furfural to Furfuryl Alcohol under Mild Condition.

Alloy structures with high catalytic surface areas and tunable surface energies can lead to high catalytic selectivity and activities. Herein, the synthesis of sponge-like Pd Pb multiframes (Pd Pb MFs) is reported by using the thermodynamically driven phase segregation, which exhibit high selectivity (93%) for the conversion of furfural to furfuryl alcohol (FOL) under mild conditions. The excellent catalytic performance of the Pd Pb MF catalysts is attributed to the high surface area and optimized surface energy of the catalyst, which is associated with the introduction of Pb to Pd.

Single-Step Fabrication of Polymeric Composite Membrane via Centrifugal Colloidal Casting for Fuel Cell Applications.

Recent interest in polymer electrolyte membranes (PEMs) for fuel cell systems has spurred the development of infiltration technology by which to insert ionomers into mechanically robust reinforcement structures by solution casting in order to produce a cost effective and highly efficient electrolyte. However, the results of the fabrication process often continue to present challenges related to the structural complexity and self-assembly dynamics between the hydrophobic and hydrophilic parts of the constituents which in turn, necessitates additional processing steps and increases production costs. Here, a single-step process is reported for highly compact polymeric composite membranes (PCMs), fabricated using a centrifugal colloidal casting (C3) method.

Current Concepts in the Management of Periodontitis.

Periodontitis is a common disorder affecting >40% of adults in the United States. Globally, the severe form of the disease has a prevalence of 11%. In advanced cases, periodontitis leads to tooth loss and reduced quality of life.

Facile one-step synthesis of Ru doped NiCoP nanoparticles as highly efficient electrocatalysts for oxygen evolution reaction.

Transition metal phosphides (TMPs) as ever-evolving electrocatalytic materials have attracted increasing attention in water splitting reactions owing to their cost-effective, highly active and stable catalytic properties. This work presents a facile synthetic route to NiCoP nanoparticles with Ru dopants which function as highly efficient electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The Ru dopants induced a high content of Ni and Co vacancies in NiCoP nanoparticles, and the more defective Ru doped NiCoP phase than undoped NiCoP ones led to a greater number of catalytically active sites and improved electrical conductivity after undergoing electrochemical activation.

Intermetallic PtCu Nanoframes as Efficient Oxygen Reduction Electrocatalysts.

Nanoframe alloy structures represent a class of high-performance catalysts for the oxygen reduction reaction (ORR), owing to their high active surface area, efficient molecular accessibility, and nanoconfinement effect. However, structural and chemical instabilities of nanoframes remain an important challenge. Here, we report the synthesis of PtCu nanoframes constructed with an atomically ordered intermetallic structure (-PtCuNF/C) showing high ORR activity, durability, and chemical stability.

Catalytic Nanoframes and Beyond.

The ever-increasing need for the production and expenditure of sustainable energy is a result of the astonishing rate of consumption of fossil fuels and the accompanying environmental problems. Emphasis is being directed to the generation of sustainable energy by the fuel cell and water splitting technologies. Accordingly, the development of highly efficient electrocatalysts has attracted significant interest, as the fuel cell and water splitting technologies are critically dependent on their performance.

Nonsurgical and surgical management of biologic complications around dental implants: peri-implant mucositis and peri-implantitis.

Biologic complications around dental implants may be categorized into peri-implant mucositis and peri-implantitis. Peri-implant mucositis is defined as reversible inflammation in the peri-implant mucosa without any apparent bone destruction. Peri-implantitis refers to inflammatory process that resulted in destruction of alveolar bone and attachment.

Potential Link between Cu Surface and Selective CO Electroreduction: Perspective on Future Electrocatalyst Designs.

Electrochemical reduction of carbon dioxide (CO RR) product distribution has been identified to be dependent on various surface factors, including the Cu facet, morphology, chemical states, doping, etc., which can alter the binding strength of key intermediates such as *CO and *OCCO during reduction. Therefore, in-depth knowledge of the Cu catalyst surface and identification of the active species under reaction conditions aid in designing efficient Cu-based electrocatalysts.

Pt-Exchanged ZIF-8 nanocube as a solid-state precursor for L1-PtZn intermetallic nanoparticles embedded in a hollow carbon nanocage.

Nanoparticles with an atomically ordered alloy phase have received enormous attention for application as catalysts in fuel cells because of their unique electronic properties resulting from unusually strong d-orbital interactions between two metal components. However, the synthesis of intermetallic nanoparticles requires a high reaction temperature, thus necessitating the protection of nanoparticles with inorganic layers to prevent aggregation of nanoparticles during synthesis. The protective layer needs to be removed later for application as a catalyst, which is a cumbersome process.

Nonsurgical periodontal therapy based on the principles of cause-related therapy: rationale and case series.

Cause-related therapy is key in the management and resolution of the two most common oral diseases: dental caries and periodontal disease. This is the first phase of treatment for those diseases. The aim is to remove, reduce, or eliminate the main causes of the disease.

RuO-decorated multimetallic hetero-nanocages as highly efficient electrocatalysts toward the methanol oxidation reaction.

Direct methanol fuel cell technology awaits the development of highly efficient and robust nanocatalysts driving the methanol oxidation reaction (MOR) in a CO poisoning-free fashion. Thus far, various Pt-based alloy nanoparticles have been studied as electrocatalysts toward the MOR, and it has been found that the introduction of dopants such as Ru and Cu to Pt has been particularly successful in mitigating the CO poisoning problem. Herein, we report a facile synthesis of Ru-branched RuPtCu nanocages that involves in situ formation of Ru-doped PtCu nanoparticles and subsequent outgrowth of Ru branches by insertion of additional Ru precursors.

Hollow nanoparticles as emerging electrocatalysts for renewable energy conversion reactions.

While the realization of clean and sustainable energy conversion systems primarily requires the development of highly efficient catalysts, one of the main issues had been designing the structure of the catalysts to fulfill minimum cost as well as maximum performance. Until now, noble metal-based nanocatalysts had shown outstanding performances toward the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). However, the scarcity and high cost of them impeded their practical use.

Ni@Ru and NiCo@Ru Core-Shell Hexagonal Nanosandwiches with a Compositionally Tunable Core and a Regioselectively Grown Shell.

The development of highly active electrocatalysts is crucial for the advancement of renewable energy conversion devices. The design of core-shell nanoparticle catalysts represents a promising approach to boost catalytic activity as well as save the use of expensive precious metals. Here, a simple, one-step synthetic route is reported to prepare hexagonal nanosandwich-shaped Ni@Ru core-shell nanoparticles (Ni@Ru HNS), in which Ru shell layers are overgrown in a regioselective manner on the top and bottom, and around the center section of a hexagonal Ni nanoplate core.

Iridium-Based Multimetallic Nanoframe@Nanoframe Structure: An Efficient and Robust Electrocatalyst toward Oxygen Evolution Reaction.

Nanoframe electrocatalysts have attracted great interest due to their inherently high active surface area per a given mass. Although recent progress has enabled the preparation of single nanoframe structures with a variety of morphologies, more complex nanoframe structures such as a double-layered nanoframe have not yet been realized. Herein, we report a rational synthetic strategy for a structurally robust Ir-based multimetallic double-layered nanoframe (DNF) structure, nanoframe@nanoframe.

A novel technique for guided bone regeneration using platelet-rich plasma and osteogenic progenitor cells: Literature-based rationale and case report.

Achieving predictable guided bone regeneration in critical size defects for future endosseous dental implant therapy poses a great challenge to clinicians. A novel technique utilizing autogenous osteogenic progenitor cells, calcium sulfate activated platelet-rich plasma in addition to particulate allograft was successfully used to augment a severely deficient maxillary anterior edentulous ridge. After 6 months of healing, satisfactory radiographic and clinical bone gain was noted with significant increase in alveolar ridge width.

Successful nonsurgical management of post-orthodontic gingival enlargement with intensive cause-related periodontal therapy.

Successful nonsurgical management of severe postorthodontic gingival enlargement and erythema in a 24-year-old male is presented. The patient received an intensive cause-related periodontal therapy, consisting of oral hygiene instruction, scaling and root planing, and weekly recall visits. At week five, complete resolution of the lesions was achieved.

Systematic review of short- (5-10 years) and long-term (10 years or more) survival and success of full-arch fixed dental hybrid prostheses and supporting implants.

Objectives: The aim of this systematic review was to investigate the short-term (5-10 year mean follow-up) and long-term (10 year or more) survival and success of fixed full arch dental hybrid prosthesis and supporting dental implants.

Methods: Studies reporting interventions with full-arch fixed dental hybrid prostheses were identified by searching PubMed/Medline (NCBI), Web of Science (Thomson Reuters), the Cochrane Register of Controlled Clinical Trials (EBSCO), and Dentistry and Oral Sciences Source (DOSS; EBSCO) from the earliest available dates through July 17, 2013. Through a series of review process by two examiners, potentially qualifying studies were identified and assessed with respect to the inclusion criteria.

Cause-related therapy: a review and suggested guidelines.

The two most common forms of oral disease, dental caries and periodontal disease, share their main etiologic factor, dental plaque. By specifically targeting their main etiologic factor, bacteria in dental plaque, cause-related therapy allows clinicians and patients to achieve successful control of these diseases. Clinicians should continuously guide and educate patients to understand the pathophysiology of their diseases so that patients will actively participate in the therapy by mechanically removing dental plaque at home.