EcoEnergy最新文献

Carbonyl sulfide represents a significant organic sulfur impurity in furnace gas, and its removal can enhance the economic value of furnace gas. In this study, a series of Al-based core–shell nanofiber catalysts were synthesized and employed for the catalytic hydrolysis of COS. The Al₂O₃@Cu-Ce catalyst demonstrated a 100% COS conversion efficiency at a gas hourly space velocity of 15 000 h⁻¹ at 70°C. The interaction of Cu and Ce can enhance their dispersion and facilitate the formation of micropores. The formation of Cu₂Al₄O₇ and CeAlO₃ resulted in a reduction in the number of micropores and effective active components on the catalyst surface. The primary catalytic roles were played by Cu²⁺ and Ce³⁺. The high content of adsorbed state oxygen O_β and suitable water resistance resulted in enhanced hydrolysis performance. The Al₂O₃ shell layer is capable of effectively protecting the Cu and Ce components from being covered and consumed, thereby prolonging the lifetime of the catalyst. The addition of Cu resulted in alterations to both the weakly and moderately basic sites, whereas the addition of Ce primarily affected the weakly basic sites. The formation of Cu-O-Ce increased the percentage of CuO in the Cu fraction, thereby enhancing the COS removal performance. There is a competitive adsorption relationship between COS and H₂S on the CuO (002) surface. COS, H₂O, and H₂S compete for adsorption on the O_v-CeO₂ (111) surface. O_v-CeO₂ (111) promotes the dissociation of H₂O and the generation of -SH groups. The hydrolysis process of COS occurs in steps on CuO (002) and O_v-CeO₂ (111).

The post-synthesis metal exchange (PSME) strategy receives substantial attention in the construction of heterometallic mental-organic frameworks (MOFs). However, traditional PSME methods encounter challenges such as prolonged solvothermal incubation and difficulties in introducing secondary metal elements. Thus, developing a rapid, sustainable, and scaled-up PSME approach for MOFs is essential. Herein, we present a mechanochemical-assisted defect engineering strategy that accelerates the PSME process (mechano-PSME). Characterization techniques demonstrate that this strategy swiftly overcomes the energy barriers of the parent MOFs, resulting in the formation of an abundance of defects. This creates an optimal environment for incorporating heterometallics, thus facilitating rapid, batch PSME of MOFs. The experimental results clearly validate the effectiveness of mechano-PSME in producing bimetallic Zr/Hf-based UiO-66, a process challenging to achieve under solvothermal conditions. Additionally, the Zr/Hf-based UiO-66 exhibits improved acidic functionality and exceptional catalytic efficiency in the esterification of levulinic acid. This research paves the way for the sustainable development of functional materials and outlines an ambitious blueprint for innovating multifunctional materials.

Cathodic protection (CP) is widely employed to mitigate metal corrosion for underground and marine facilities, but the implementation of conventional sacrificial anode CP (SACP) and impressed current CP (ICCP) is obstructed by drawbacks such as release of harmful substances, continuous external power supply, and complicated maintenance. Although solar-powered CP systems have emerged to replace conventional systems, the available technical routes are far from perfect: the efficiencies of semiconductor-based small photoelectrochemical devices are still low, and ICCP systems driven by photovoltaic (PV) cells are often large in size and high in cost. Herein, a portable CP device (30 × 30 × 20 cm³ and 5.1 kg) with a modular design has been constructed, the fully functioning of which is solely powered by a PV cell without any external electricity input. A real-time “monitoring-feedback-adjustment” mechanism was modulated by a cost-effective and multifunctional microprocessor to precisely maintain the metal potential within the protective potential range. Moreover, a lab-made noble-metal-free auxiliary anode composed of porous Ni foam coated with NiMo alloy was first introduced to the PV-driven ICCP system, which accelerated the water oxidation kinetics compared to various commercial anodes and elevated the overall energy efficiency. Consequently, the as-built SMPCPD was capable of providing continuous CP to three types of representative metals in natural seawater under outdoor sunlight illumination conditions. These findings represent a variable pathway to achieve CP of underwater and underground steel structures with zero carbon emission, no environmental toxicity, intelligent control, high-energy efficiency, and flexibility.

With the increasing global energy demand and the growing issues of environmental pollution and climate change, the development of clean and sustainable energy conversion technologies has become particularly important. The use of traditional fossil fuels has put immense pressure on the environment and brought about challenges related to energy security and climate change. Therefore, researching alternative energy sources and green catalytic technologies has become key to solving these problems. Among various sustainable energy technologies, reactions such as hydrogen production, carbon dioxide reduction, nitrogen reduction, and oxygen reduction play a crucial role in the conversion and storage of clean energy. However, traditional catalysts face challenges in efficiency, selectivity, and stability, which limit their commercialization process. Single-atom catalysts (SACs), as a new type of catalyst, have shown excellent catalytic performance due to their high surface area and precise control of active sites, significantly reducing catalytic costs. SACs have performed well in water splitting, carbon dioxide reduction, nitrogen reduction, and oxygen reduction reactions, but their application still faces challenges such as synthesis complexity, stability issues, and a deep understanding of catalytic mechanisms. This article explores the key role of SACs in sustainable energy conversion, analyzes their application in various energy conversion reactions, evaluates performance enhancement strategies, and discusses the challenges they face and their future prospects. Through a comprehensive analysis, this article aims to provide an in-depth understanding of the application of SACs in the energy field, promoting technological advancement and commercial application in this area.

Self-assembled monolayers (SAMs) have received increasing interest in the application of perovskite photovoltaics (PV). However, the deposition of SAMs in most of the studies rely on spin-coating, which is impractical for upscaling applications. In this work, the dip-coating deposition of SAMs is studied for application in p-i-n structured perovskite solar cells. It is found that the dip-coating can not only replace spin-coating in device fabrication but also provide improved uniformity and density of the SAM compared to spin-coating, which leads to enhanced charge extraction with reduced interface defects. Consequently, the perovskite solar cells prepared with the dip-coated SAM demonstrates an improved power conversion efficiency of 23.5%, providing a new pathway for the commercialization of SAMs-based perovskite.

Sodium-ion batteries are considered one of the most promising candidates for lithium-ion batteries. Increasing charging voltage is an effective way to realize sodium-ion batteries with low cost and high energy density. However, the narrow voltage window of the existing electrolyte is a serious constraint. This review systematically summarizes the development of electrolytes for high-voltage sodium-ion batteries in recent years. Firstly, the basic characteristics and critical influencing factors of high-voltage electrolytes are presented. Secondly, the strategies of developing high-voltage sodium-ion electrolytes in recent years are systematically summarized, including the regulation of solvation structure, the characteristics and applications of new high voltage resistant solvents, and the action mechanism of high-voltage additives. Finally, the future development trend of sodium-ion high-voltage electrolytes is proposed, aiming to promote the breakthrough and application of high energy density sodium-ion batteries.

Hydrogen serves as an ideal clean energy with zero carbon emissions, whereas its large-scale application relies on its liquidation, by which the catalytic conversion of ortho–para H₂ at cryogenic temperature is inevitable with iron oxides as a promising catalyst. In this research, iron oxides with varied surface area and diverse phases were synthesized from the precursor of hydrous ferric oxide, including α-Fe₂O₃, γ-Fe₂O₃, and Fe₃O₄. The bulk and surface properties of these catalysts were characterized by XRD, BET, TG, IR, magnetic analysis, hydrogen adsorption, and ⁵⁷Fe-Mössbauer spectrum. It was suggested that ortho–para H₂ conversion is linearly correlated with the specific surface area of α-Fe₂O₃ which governs the residual magnetic properties as well as the adsorption capacity of molecular H₂ on the catalysts, and a nondissociation mechanism of ortho–para H₂ conversion was revealed at cryogenic temperature. The hydrate that contributed to the surface area of iron oxides shows a negative effect on the ortho–para H₂ conversion. Moreover, by estimating the reaction rate based on the per surface area of iron oxides, the Fe(III) exposed on surfaces exhibited a superior activity irrespective of the bulk magnetism of iron oxides, and the intrinsic activity of iron oxides for ortho–para H₂ conversion was found to follow a trend similar to that of α-Fe₂O₃ ≈ γ-Fe₂O₃ > Fe₃O₄. The findings of this study provide valuable insights for the subsequent research on the mechanism of ortho–para H₂ conversion and the design of high-performance hydrogen liquefaction catalysts.

Hematite is a promising candidate material for photoanodes, but the efficiency of the state-of-the-art hematite photoanodes is limited by the low absorption coefficient, short hole diffusion length, and slow water oxidation kinetics. In this work, a high-efficiency hematite photoanode was designed and fabricated by introducing titanium-doped hematite (Ti:Fe₂O₃) homojunction with different doping contents and a hierarchical nanorod/nanobowl array structure. The homojuction consisted of low Ti doping nanorods grown on high Ti doping nanobowl arrays, leading to the formation of a broad built-in electric field, significantly enhancing the charge separation and transfer within the bulk. Furthermore, the nanorods radially grown inside the bowls and on the bowl edges enabled enhanced light absorption through multiple light scattering while offering a larger electrode–electrolyte contact area and providing more reaction sites. Compared to the Ti:Fe₂O₃ nanorod arrays, the Ti:Fe₂O₃ nanorod/nanobowl array photoanode exhibited an increase in photocurrent density from 1.6 mA cm⁻² to 3.0 mA cm⁻² at 1.23 V versus RHE, maintaining long-term stability over 100 h at 1.23 V versus RHE. This study not only achieved a high-performance hematite photoanode but also provided a new perspective on the design of differently doping homojunction photoanodes with desired nanostructures.

Heterostructure catalyst is highly efficient for photoelectrolytic (PEC) wastewater remediation, while rationally constructing the photoelectrocatalyst with a high-quality interface is still challenging. Herein, a simple hydrothermal process prepares a heterostructure NiMoO₄@α-MnO₂ with a uniform interface between NiMoO₄ nanosheets and α-MnO₂ nanowires. NiMoO₄@α-MnO₂ exhibited significant advantages as follows: (1) α-MnO₂ nanowires act as charge transport channels like the arteries that transport nutrients, promoting the migration and separation of induced charges; (2) the pollutants can be electrostatically concentrated to the surface of the NiMoO₄@α-MnO₂. Specifically, the gossamer-like NiMoO₄ nanosheets adhering on the surface of the α-MnO₂ have a large surface area, beneficial for electrolyte penetration and utilization of active sites. (3) Unfolded gossamer-like NiMoO₄, like a vast extended solar panel of an artificial satellite, can harvest more solar energy, generating lots of electron (e⁻)/hole (h⁺) pairs and active species, offering multiple transfer pathways and speeding up the rate of the degradation reaction. The optimized heterostructured NiMoO₄@α-MnO₂-3.5 catalysts showed superior PEC activity and remarkable stability for degrading reactive brilliant blue KN-R. Z-scheme heterojunction between α-MnO₂ and NiMoO₄ is proposed based on their energy band structure and free radical quenching experiment.

Solid–solid phase change materials usually suffer from the challenges of low thermal storage capacity and poor mechanical strength in thermal management applications. Additionally, solid–solid phase change materials are often prepared by a chemical cross-linking strategy, leading to poor recyclability. This study highlights a straightforward and effective strategy to prepare multiple H-bonding cross-linking supramolecular solid–solid phase change materials integrating easy recyclability, high mechanical strength, and high latent heat characteristics for thermal management of lithium batteries.