Porous N, P co-doped carbon-coated ultrafine Co2P nanoparticles derived from DNA: An electrocatalyst for highly efficient hydrogen evolution reaction

Superhydrophilic/superaerophobic CoP/CoMoO4 multi-level hierarchitecture electrocatalyst for urea-assisted hydrogen evolution reaction in alkaline media

Utilizing the thermodynamically favorable urea oxidation reaction instead of the anodic oxygen precipitation reaction is an alternative pathway for the energy-saving hydrogen production. Therefore, it is significant to explore advanced electrocatalysts for both HER and UOR. In this work, a dendritic heteroarchitectures of 2D CoMoO4 nanosheets deposited on 1D CoP nanoneedles (CoP/CoMoO4-CC) was fabricated as bifunctional electrocatalyst. 1D CoP nanostructure with fast charge transport pathways and 2D CoMoO4 nanostructure with large specific surface area and short paths for electron/mass transport. The unique morphology endows the superhydrophilic and superaerophobic properties, allowing for the rapid contact with the reactants and rapid removal of surface-generated gases. As a result, the CoP/CoMoO4-CC shows efficient bifunctional activity. This work offers a new avenue to rationally design bifunctional electrocatalysts for large-scale practical hydrogen production.

Spaced-Confined Janus Engineering Enables Controlled Ion Transport Channels and Accelerated Kinetics for Secondary Ion Batteries

The large grain boundary resistance between different components of the anode electrode easily leads to the low ion transport efficiency and poor electrochemical performance of lithium-/sodium-ion batteries (LIBs/SIBs). To address the issue, a Janus heterointerface with a Mott-Schottky structure is proposed to optimize the interface atomic structure, weaken interatomic resistance, and improve ion transport kinetics. Herein, Janus Co/Co2P@carbon-nanotubes@core-shell (Janus Co/Co2P@CNT-CS) refined urchin-like architecture derived from metal-organic frameworks is reported via a coating-phosphating process, where the Janus Co/Co2P heterointerface nanoparticles are confined in carbon nanotubes and a core-shell polyhedron. Such a Janus Co/Co2P heterointerface shows the strong built-in electric field, facilitating the controllable ion transport channels and the high ion transport efficiency. The Janus Co/Co2P@CNT-CS refined urchin-like architecture composed of a core-shell structure and the grafting carbon nanotubes enhances the structure stability and electronic conductivity. Benefiting from the spaced-confined Janus heterointerface engineering and synergistic effects between the core-shell structure and the grafting carbon nanotubes, the Janus Co/Co2P@CNT-CS refined urchin-like architecture demonstrates the fast ion transport rate and excellent pseudocapacitance performance for LIBs/SIBs. In this case, the Janus Co/Co2P@CNT-CS refined urchin-like architecture shows high specific capacities of 709 mA h g-1 (200 cycles) and 203 mA h g-1 (300 cycles) at a current density of 500 mA g-1 for LIBs/SIBs, respectively.

Waste biomass-derived N, P co-doping carbon aerogel-coated CoxFe1-xP with modulated electron density for efficient electrooxidation of contaminants

Developing low-cost, green, high-performing electrode materials to address environmental pollutants and the energy crisis is significant but challenging. Herein, the bimetallic iron cobalt phosphide coated in waste biomass-derived N, P co-doping carbon (CoxFe1-xP@NPC) is constructed. Furthermore, the active site density and the water decomposition energy barrier of surface-coated NPC are modulated by optimizing the electronic structure of CoxFe1-xP via doping engineering. The Fe-modulated CoxFe1-xP@NPC exhibits a hierarchical porous self-supporting structure and excellent physical & chemical properties with excellent electrooxidation performance, achieving over 95% removal of TCH within 60 min. The density functional theory (DFT) calculations further confirms that N carries more positive charge and P carries more negative charge in the NPC of CoxFe1-xP@NPC with Fe modulation, which can promote the adsorption and dissociation of water molecules. Of note, Co0.75Fe025P@NPC displays a low water dissociation energy barrier to produce ·OH and a high energy barrier to produce O2 than its counterparts. This study offers new insight into controllable modulation of biomass carbon-based composite electrode catalytic activity for high-efficiency degradation of contaminants.

A Green Synthesis Strategy for Cobalt Phosphide Deposited on N, P Co-Doped Graphene for Efficient Hydrogen Evolution

The exploitation of electrocatalysts with high activity and durability for the hydrogen evolution reaction is significant but also challenging for future energy systems. Transition metal phosphides (TMPs) have attracted a lot of attention due to their effective activity for the hydrogen evolution reaction, but the complicated preparation of metal phosphides remains a bottleneck. In this study, a green fabrication method is designed and proposed to construct N, P co-doped graphene (NPG)-supported cobalt phosphide (Co2P) nanoparticles by using DNA as both N and P sources. Thanks to the synergistic effect of NPG and Co2P, the Co2P/NPG shows effective activity with a small overpotential of 144 mV and a low Tafel slope of 72 mV dec-1 for the hydrogen evolution reaction. This study describes a successful green synthesis strategy for the preparation of high-performance TMPs.

Transition Metal Phosphide Nanoarchitectonics for Versatile Organic Catalysis

Transition metal phosphides (TMP) posses unique physiochemical, geometrical, and electronic properties, which can be exploited for different catalytic applications, such as photocatalysis, electrocatalysis, organic catalysis, etc. Among others, the use of TMP for organic catalysis is less explored and still facing many complex challenges, which necessitate the development of sustainable catalytic reaction protocols demonstrating high selectivity and yield of the desired molecules of high significance. In this regard, the controlled synthesis of TMP-based catalysts and thorough investigations of underlying reaction mechanisms can provide deeper insights toward practical achievement of desired applications. This review aims at providing a comprehensive analysis on the recent advancements in the synthetic strategies for the tailored and tunable engineering of structural, geometrical, and electronic properties of TMP. In addition, their unprecedented catalytic potential toward different organic transformation reactions is succinctly summarized and critically analyzed. Finally, a rational perspective on future opportunities and challenges in the emerging field of organic catalysis is provided. On the account of the recent achievements accomplished in organic synthesis using TMP, it is highly anticipated that the use of TMP combined with advanced innovative technologies and methodologies can pave the way toward large scale realization of organic catalysis.