Synergistic Roles of the CoO/Co Heterostructure and Pt Single Atoms for High-Efficiency Electrocatalytic Hydrogenation of Lignin-Derived Bio-Oils

Electrochemical hydrogeneration (ECH) of biomass-derived platform molecules, which avoids the disadvantages in utilizing fossil fuel and gaseous hydrogen, is a promising route toward value-added chemicals production. Herein, we reported a CoO/Co heterostructure-supported Pt single atoms electrocatalyst (Pt1-CoO/Co) that exhibited an outstanding performance with a high conversion (>99%), a high Faradaic efficiency (87.6%), and robust stability (24 recyclability) at −20 mA/cm2 for electrochemical phenol hydrogenation to high-valued KA oil (a mixture of cyclohexanol and cyclohexanone). Experimental results and the density functional theory calculations demonstrated that Pt1-CoO/Co presented strong adsorption of phenol and hydrogen on the catalyst surface simultaneously, which was conducive to the transfer of the adsorbed hydrogen generated on the single atom Pt sites to activated phenol, and then, ECH of phenol with high performance was achieved instead of the direct hydrogen evolution reaction. This work described that the multicomponent synergistic single atom catalysts could effectively accelerate the ECH of phenol, which could help the achievement of large-scale biomass upgrading

Facile Synthesis of Defect-Rich and S/N Co-Doped Graphene-Like Carbon Nanosheets as an Efficient Electrocatalyst for Primary and All-Solid-State Zn–Air Batteries

Developing facile and low-cost porous graphene-based catalysts for highly efficient oxygen reduction reaction (ORR) remains an important matter for fuel cells. Here, a defect-enriched and dual heteroatom (S and N) doped hierarchically porous graphene-like carbon nanomaterial (D-S/N-GLC) was prepared by a simple and scalable strategy, and exhibits an outperformed ORR activity and stability as compared to commercial Pt/C catalyst in an alkaline condition (its half-wave potential is nearly 24 mV more positive than Pt/C). The excellent ORR performance of the catalyst can be attributed to the synergistic effect, which integrates the novel graphene-like architectures, 3D hierarchically porous structure, superhigh surface area, high content of active dopants, and abundant defective sites in D-S/N-GLC. As a result, the developed catalysts are used as the air electrode for primary and all-solid-state Zn–air batteries. The primary batteries demonstrate a higher peak power density of 252 mW cm^–2 and high voltage of 1.32 and 1.24 V at discharge current densities of 5 and 20 mA cm^–2, respectively. Remarkably, the all-solid-state battery also exhibits a high peak power density of 81 mW cm^–2 with good discharge performance. Moreover, such catalyst possesses a comparable ORR activity and higher stability than Pt/C in acidic condition. The present work not only provides a facile but cost-efficient strategy toward preparation of graphene-based materials, but also inspires an idea for promoting the electrocatalytic activity of carbon-based materials

Linear correlations between LBP level and M value.

<p>Linear correlations between LBP level and M value.</p

Serum LBP concentrations between PCOS and controls.

<p>Serum LBP concentrations between PCOS and controls.</p

Self-Organized 3D Porous Graphene Dual-Doped with Biomass-Sponsored Nitrogen and Sulfur for Oxygen Reduction and Evolution

3D graphene-based materials offer immense potentials to overcome the challenges related to the functionality, performance, cost, and stability of fuel cell electrocatalysts. Herein, a nitrogen (N) and sulfur (S) dual-doped 3D porous graphene catalyst is synthesized via a single-row pyrolysis using biomass as solitary source for both N and S, and structure directing agent. The thermochemical reaction of biomass functional groups with graphene oxide facilitates in situ generation of reactive N and S species, stimulating the graphene layers to reorganize into a trimodal 3D porous assembly. The resultant catalyst exhibits high ORR and OER performance superior to similar materials obtained through toxic chemicals and multistep routes. Its stability and tolerance to CO and methanol oxidation molecules are far superior to commercial Pt/C. The dynamics governing the structural transformation and the enhanced catalytic activity in both alkaline and acidic media are discussed. This work offers a unique approach for rapid synthesis of a dual-heteroatom doped 3D porous-graphene-architecture for wider applications

In Situ Nitrogen Infiltration into an Ordered Pt₃Co Alloy with sp–d Hybridization to Boost Fuel Cell Performance

Reducing the dosage of Pt while achieving high activity and stability remains a significant challenge in developing a cathode catalyst for the H2/air-fed fuel cell. Here, we employed N-doped carbon derived from small organic molecules as N sources to prepare a fully N-doped ordered Pt3Co catalyst (IM-Pt3CoN) for the oxygen reduction reaction (ORR). This unique approach precisely controls the in situ capture of N atoms during the high-temperature alloying process of ordered Pt3Co nanoparticles (NPs), allowing full interstitial doping of N atoms within the gaps of Pt3Co intermetallic nanocrystals. The nitrogen-implanted IM-Pt3Co with increased vacancy formation energy of Pt/Co and optimized d band can restrain the tendency of Pt/Co dissolution and weaken the binding of oxygenated species, leading to improved ORR activity and durability. Remarkably, the IM-Pt3CoN catalyst demonstrated high performance in the H2–O2 fuel cell (a high power density of 2.4 W cm–2, 1.21 A/mgPt for mass activity (MA)) and enhanced stability (78.7% MA retained after 30k voltage cycles). Furthermore, in practical H2–air fuel cell tests, a peak power density of 1.01 W cm–2 and a voltage loss of only 28 mV at 0.8 A cm–2 after an accelerated durability test (ADT) can be achieved. These performance indicators exceed the Department of Energy (DOE) 2025 fuel cell technical targets