EcoEnergy最新文献

Photoelectrochemical (PEC) water splitting with zero carbon emissions is a promising technology to solve the global issues of energy shortage and environmental pollution. However, the current development of PEC systems is facing a bottleneck of low solar-to-hydrogen (STH) efficiency (<10%), which cannot meet the demand of large-scale H₂ production. The development of low-cost, highly active, and stable photoanode materials is crucial for high STH efficiency of PEC water splitting. The recent development of BiVO₄ as photoanode materials for PEC water splitting has been a great success, and ABO₄-type ternary metal oxides with a similar structure to BiVO₄ have high development potential as efficient photoanodes for high-performance PEC water splitting. The design and development of ABO₄ photoanodes for PEC water splitting are critically reviewed with special emphasis on the modification strategies and performance improvement mechanisms of each semiconductor. The comprehensive analysis in this review provides guidelines and insights for the exploration of new high-efficiency photoanodes for solar fuel production.

Metal-nitrogen-doped carbon material have sparked enormous attentions as they show excellent electrocatalytic performance and provide a prototype for mechanistic understandings of electrocatalytic reactions. Researchers spare no effort to find catalytic reactivity “descriptor”, which is correlated with catalytical properties and could be utilized for guiding the rational design of high-performance catalysts. In recent years, benefited from the development of computational technology, theoretical calculation came into being as a powerful tool to understand catalytic mechanisms from an atomic level as well as to accelerate the process of finding a catalytic reactivity descriptor and promoting the development of effective catalysts. In the present review, we provide the latest theoretical research toward energetic and electronic descriptors for metal-nitrogen-doped carbon (M-N-C) materials, which have shown excellent electrocatalytic performance and provide a prototype for the mechanistic understanding of electrocatalytic reactions. This review uses density functional theory calculation and the most advanced machine learning method to describe the exploration of four kinds of electrocatalytic reaction descriptors, namely oxygen reduction reaction, carbon dioxide reduction reaction, hydrogen evolution reaction, and nitrogen reduction reaction. The aim of this review is to inspire the future design of high-efficiency M-N-C catalysts by providing in-depth insights into the electrocatalytic activity of these materials.

Liquid organic hydrogen carriers have emerged as promising hydrogen storage systems, offering notable advantages over conventional storage and utilization efficiency methods. However, designing a catalyst that operates at low temperatures and remains cost-effective poses a significant challenge. We successfully synthesized Pd species (single atoms, fully exposed clusters, and nanoparticles) on a nanodiamond/graphene (ND@G) hybrid support for toluene hydrogenation. The structure of as-developed Pd catalyst was investigated by HAADF-STEM, X-ray absorption fine structure, Raman, XRD, XPS, and other characterizations. Remarkably, the Pd_n/ND@G catalyst achieved a toluene conversion rate of 99.3% (100°C, 2.0 MPa H₂) without loss of catalytic ability after 5 runs, which exhibited excellent catalytic performance and stable activity. Furthermore, the Pd_n/ND@G catalyst exhibited an apparent activation energy as low as 62.36 ± 3.33 kJ mol⁻¹ and an initial turnover frequency of 33.1 h⁻¹ at 100°C. By adjusting the size and metal-dependent effects, we have achieved enhanced catalytic performance for toluene hydrogenation, thus paving the way for the design of efficient liquid organic hydrogen storage catalysts.

Ammonia (NH₃) has received significant attention due to its increasing demand as a key commodity for industrial chemical production, a green fuel, and a hydrogen (H₂) carrier. Electrochemical nitrogen (N₂) reduction reaction (ENRR) emerges as the most attractive pathway to produce NH₃. The process utilizes H₂O as a proton source under mild temperature and pressure, which can reduce CO₂ emissions and energy input compared to the traditional Haber-Bosch process. However, ENRR is severely insufficient for practical applications due to its kinetically sluggish steps compared to its competitive hydrogen evolution reaction. Also, the imbalanced reactant concentrations of N₂ and H₂O, resulting from the low N₂ solubility, and oppositely, free H₂O accessibility toward catalysts, cause the ineffective three-phase-boundary that acts as active sites for ENRR. To overcome these challenges, it is essential to perform interfacial engineering for each part of the catalyst and reaction environment. In this perspective, recent advances in interfacial engineering are examined and critically reviewed, and further research directions are proposed to develop ENRR significantly. The sections cover catalytic active site modification, hydrophobic/hydrophilic control, electrolyte engineering, and system design. The insights and prospects in this perspective will be effective for developing ENRR in a scientific and practical manner.