Heteroatom-Doped Carbon Materials for Multifunctional Noncatalytic Applications.

The introduction of heteroatoms (i.e., atoms different from the carbon atom) with different sizes and electronegativities into a pure carbon structure offers a way to control the electron distribution within carbon materials.

Enhancing Oxygen Transport in Proton Exchange Membrane Fuel Cell Through Nanoconfined Triple Phase Interface Engineering.

In proton exchange membrane fuel cells (PEMFCs), ionomer aggregation on Pt/C catalysts leads to increased oxygen transport resistance of conventional catalyst layers. This behavior significantly influences oxygen transport in the microenvironment at the triple-phase interface of Pt/C catalysts. To address this challenge, triazine-based covalent organic frameworks (COFs) were incorporated into the cathode catalyst layer, so that their well-defined pore structure and proton eligible triazine sites interact with terminal sulfonate groups of the Nafion ionomer.

Nanoparticle-enabled molecular imaging diagnosis of osteoarthritis.

Osteoarthritis (OA) is the most common type of arthritis and affects patients with chronic pain, while imposing a heavy burden on public health systems worldwide. Current imaging technologies such as X-ray, MRI, and CT assist the diagnosis and monitoring of OA by providing anatomical pathological information. However, given the complex nature and progression of OA, conventional imaging technologies are limited in the molecular pathological information they are able to present and identify from the various health conditions of OA patients.

Metal-Free Carbon Co-Catalysts for Up-Conversion Photo-Induced Catalytic Cancer Therapy.

Near-infrared (NIR)-responsive metal-free carbon co-catalysts that convert glucose into HO to generate reactive oxygen species (ROS) are developed from phosphorus-doped carbon nitride (P-CN) and graphene quantum dots (GQD) composites, for enhanced photocatalytic cancer therapy by light exposure in the targeted tumor microenvironment. Upon irradiation, the NIR light is converted by GQD with up-conversion function into visible light to excite P-CN for photocatalytic conversion of glucose into HO, which subsequently decomposes into ROS. ROS thus generated exhibits an excellent anticancer efficacy for efficient cancer therapy with minimal side effects, as evidenced by both in vitro and in vivo studies.

Carbon-based metal-free electrocatalysts: from oxygen reduction to multifunctional electrocatalysis.

Since the discovery of N-doped carbon nanotubes as the first carbon-based metal-free electrocatalyst (C-MFEC) for oxygen reduction reaction (ORR) in 2009, C-MFECs have shown multifunctional electrocatalytic activities for many reactions beyond ORR, such as oxygen evolution reaction (OER), hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CORR), nitrogen reduction reaction (NRR), and hydrogen peroxide production reaction (HOPR). Consequently, C-MFECs have attracted a great deal of interest for various applications, including metal-air batteries, water splitting devices, regenerative fuel cells, solar cells, fuel and chemical production, water purification, to mention a few. By altering the electronic configuration and/or modulating their spin angular momentum, both heteroatom(s) doping and structural defects (, atomic vacancy, edge) have been demonstrated to create catalytic active sites in the skeleton of graphitic carbon materials.

C-Adsorbed Single-Walled Carbon Nanotubes as Metal-Free, pH-Universal, and Multifunctional Catalysts for Oxygen Reduction, Oxygen Evolution, and Hydrogen Evolution.

Buckminsterfullerene (C) was adsorbed onto single-walled carbon nanotubes (SWCNTs) as an electron-acceptor to induce intermolecular charge-transfer with the SWCNTs, leading to a class of new metal-free C-SWCNT electrocatalysts. For the first time, these newly developed C-SWCNTs were demonstrated to act as trifunctional metal-free catalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) over a wide range of pH values, from acid to alkaline, with even higher electrocatalytic activities and better long-term stabilities than those of commercial Pt and RuO counterparts. Thus, the adsorption-induced intermolecular charge-transfer with the C electron-acceptor can provide a general approach to high-performance, metal-free, pH-universal carbon-based trifunctional metal-free electrocatalysts for water-splitting and beyond.

Nanoparticle based simple electrochemical biosensor platform for profiling of protein-nucleic acid interactions.

The analysis of protein-nucleic acid interactions is essential for biophysics related research. However, simple, rapid, and accurate methods for quantitative analysis of biomolecular interactions are lacking. We herein establish an electrochemical biosensor approach for protein-nucleic acid binding analysis.

Novel MOF-Derived Co@N-C Bifunctional Catalysts for Highly Efficient Zn-Air Batteries and Water Splitting.

Metal-organic frameworks (MOFs) and MOF-derived materials have recently attracted considerable interest as alternatives to noble-metal electrocatalysts. Herein, the rational design and synthesis of a new class of Co@N-C materials (C-MOF-C2-T) from a pair of enantiotopic chiral 3D MOFs by pyrolysis at temperature T is reported. The newly developed C-MOF-C2-900 with a unique 3D hierarchical rodlike structure, consisting of homogeneously distributed cobalt nanoparticles encapsulated by partially graphitized N-doped carbon rings along the rod length, exhibits higher electrocatalytic activities for oxygen reduction and oxygen evolution reactions (ORR and OER) than that of commercial Pt/C and RuO , respectively.

Edge Functionalization of Graphene and Two-Dimensional Covalent Organic Polymers for Energy Conversion and Storage.

Edge functionalization by selectively attaching chemical moieties at the edge of graphene sheets with minimal damage of the carbon basal plane can impart solubility, film-forming capability, and electrocatalytic activity, while largely retaining the physicochemical properties of the pristine graphene. The resultant edge-functionalized graphene materials (EFGs) are attractive for various potential applications. Here, a focused, concise review on the synthesis of EFGs is presented, along with their 2D covalent organic polymer (2D COP) analogues, as energy materials.

Oxidizing metal ions with graphene oxide: the in situ formation of magnetic nanoparticles on self-reduced graphene sheets for multifunctional applications.

Fe(2+) cations in FeCl(2) or FeSO(4) were oxidized by graphene oxide, leading to an in situ deposition of Fe(3)O(4) nanoparticles onto the self-reduced graphene oxide (rGO) sheets. The resultant Fe(3)O(4)/rGO sheets were demonstrated to possess interesting magnetic and electrochemical properties attractive for a large variety of potential applications.