N, P dual-doped hollow carbon spheres supported MoS2 hybrid electrocatalyst for enhanced hydrogen evolution reaction

Nano bowl-like cobalt-cobalt molybdenum carbide coated by N,P co-doped carbon as an advanced bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries

Nano bowl-like Co-Co₆Mo₆C₂ coated by N,P co-doped carbon (Co-Co₆Mo₆C₂@NPC) is reported as an electrocatalyst for Zn-air batteries. Co-Co₆Mo₆C₂@NPC only needs an overpotential of 210 mV at 10 mA cm^-2 for the OER, and the half-wave potential for the ORR is 0.81 V. In addition, the Co-Co₆Mo₆C₂@NPC based battery shows a large open-circuit voltage of 1.335 V and a maximum power density of 160.5 mW cm^-2, as well as good stability. The improved catalytic performance can be ascribed to the co-existence of Co₆Mo₆C₂ and Co species to improve the intrinsic catalytic activity, and the bowl-like nanostructure to facilitate the mass transfer.

Activation Strategy of MoS2 as HER Electrocatalyst through Doping-Induced Lattice Strain, Band Gap Engineering, and Active Crystal Plane Design

Doping engineering emerges as a contemporary technique to investigate the catalytic performance of MoS₂. Cation and anion co-doping appears as an advanced route toward electrocatalytic hydrogen evolution reaction (HER). V and N as dopants in MoS₂ (VNMS) build up a strain inside the crystal structure and narrow down the optical band gaps manifesting the shifting of the absorbance band toward lower energy and improved catalytic performance. FE-SEM, HR-TEM, and XRD analysis confirmed that V and N doping decreases agglomeration possibility, particle size, developed strain, and crystal defects during crystal growth. Frequency shift and peak broadening in Raman spectra confirmed the doping induced strain generation in MoS₂ leading to the modification of acidic and alkaline HER (51 and 110 mV @ 10 mAcm^-2, respectively) performance. The improved donor density in VNMS was confirmed by the Mott-Schottky analysis. Enhanced electrical conductivity and optimized electronic structures facilities H* adsorption/desorption in the catalytically active (001) plane of cation and anion co-doped MoS₂.

Cobalt disulfide supported on porous carbon foam as a high performance hydrogen evolution reaction catalyst

An excellent cobalt disulfide–carbon foam composite catalyst was synthesized by a hydrothermal method for the electrochemical hydrogen evolution reaction (HER).

Construction of MoO2@MoS2 heterostructures in situ on carbon cloth for the hydrogen evolution reaction

MoO2@MoS2 heterostructures in situ grown on carbon cloth were developed for efficient hydrogen evolution reaction.

Activation of Humic Acid in Lignite Using Molybdate-Phosphorus Hierarchical Hollow Nanosphere Catalyst Oxidation: Molecular Characterization and Rice Seed Germination-Promoting Performances

Although solid-phase activation of lignite using a nanocatalyst has great potential in producing low-cost and sustainable humic acid, the large-scale application of this technology still faces challenges because of the high price and toxicity of the nanocatalyst. Additionally, the specific molecular components of humic acid in activated lignite remain unknown. In this work, a multifunctional molybdate-phosphorus hierarchical hollow nanosphere (Mo-P-HH) catalyst was successfully manufactured by a simple way followed by phosphorization. In comparison with a commercial Pd/C catalyst, the multifunctional Mo-P-HH catalyst was more effective in producing water-soluble humic acid with small molecular functional groups from lignite via solid-phase activation. Moreover, Fourier transform ion cyclotron resonance mass spectrometry revealed the molecular compositions of humic acid in activated lignite. Compared with that from raw lignite, the humic acid after Mo-P-HH activation had less aromatic structure but higher content of lipids, proteins, amino sugar, and carbohydrates. In addition, the activated humic acid simulated seed germination and seedling growth. Therefore, this study provided a high-performance hierarchical hollow nanocatalyst for activation of humic acid and also offered the theoretical basis for the application of humic acid in agriculture.

In-situ Formation of Amorphous Co-Al-P Layer on CoAl Layered Double Hydroxide Nanoarray as Neutral Electrocatalysts for Hydrogen Evolution Reaction

Exploration of high-efficiency and inexpensive electrode catalysts is of vital importance for the hydrogen evolution reaction (HER). In this research, an amorphous Co-Al-P layer was constructed on the surface of CoAl layered double hydroxide (CoAl-LDH) via an in-situ wet phosphidation strategy. The core-shell CoAl-LDH@Co-Al-P on Ti mesh (CoAl-LDH@Co-Al-P/TM) as an active HER electrocatalyst demands an overpotential of 150 mV to achieve a current density of 10 mA cm-2 at neutral pH. Moreover, CoAl-LDH@Co-Al-P/TM also exhibits good electrochemical stability and a superior Faradic efficiency of nearly 100%.