Progress in Natural Science: Materials International最新文献

Utilizing solar energy to decompose tetracycline (TC) is a green strategy to treat wastewater. Herein, a heterogeneous hollow structured TiO₂ decorated Pt nanoparticles were successfully designed and synthesized via hard-template approach and photo-deposition process toward TC photodegradation. The Pt nanoparticles loaded on the surface of hollow structured TiO₂ can increase the visible light absorption due to the local surface plasmon resonance (LSPR) effect. Furthermore, owing to the tough electron oscillation of the LSPR excitation, the plasmonic hot holes on the surface of Pt nanoparticles can capture the electrons of TiO₂, effectively facilitating the separation of photo-excited charge carriers because of the formation of Schottky junction constructed between Pt and TiO₂. Combined the natural merits of shorten conveying path of charge carriers and physical structural stability for hollow structure, the optimal Pt/TiO₂ hetero-junction hybrid showed superior photocatalytic activity and durability for TC photodegradation with the degradation efficiency of 93.8 ​% after 30 ​min and the rate constant of 0.09196 min⁻¹ under 300 ​W Xe lamp irradiation. This work displays a heterogeneous hybrids catalyst based on eco-friendly metal and semiconductor materials which can be used in the fields including without limitation TC photodegradation.

Biomass carbon has the advantage of a wide spectral absorption range, which makes it great potential for solar thermal utilization. In this study, porous skeleton support materials of sugarcane-derived carbon were prepared by freeze-drying-high-temperature carbonization method using natural sugarcane as raw material, and the characterization results demonstrate that the porous skeleton of sugarcane-derived carbon has outstanding porous support properties. By combining CuS with sugarcane-derived carbon, a porous material with outstanding photo-thermal conversion performance was synthesized. Four photo-thermal composite phase change materials (CPCMs) were prepared, the maximum loading mass of the support material C600 to the phase change materials (PCMs) reached 79.77 ​%. The C600-CuS-OC had excellent thermal storage properties with an enthalpy of melting of 276.3 ​J/g and a thermal conductivity of 0.61 ​W·m⁻¹·K⁻¹. The photo-thermal conversion efficiency of C600-CuS-OC was 83.2 ​%. Sugarcane carbon-based CPCMs are a low-cost and high-efficiency solar thermal storage material, which has great potential for applications in solar thermal storage, biomass utilization, and thermal management.

Energy transition towards net-zero society calls for utilization of renewable power to drive CO₂ conversion in an efficient electrochemical way. The development of a commercial CO₂ electrolyzer with positive tech-eco effect calls for active and durable electrocatalysts. High-loading gold on carbon (Au/C) with reduced particle size is the prerequisite for the highly-selective and highly energy-efficient CO production in such a CO₂ electrolyzer, but a scalable synthetic method is missing. With combined control of ligand, substrate and pH value, Au/C catalysts with particle size within 5 ​nm and metal loading of 40 ​wt% and 60 ​wt% are synthesized on low and high surface-area carbon, respectively. We also provide a thorough investigation of the effect of the ligand type, surface charge of gold nanoparticles (Au NPs) and surface area of carbon substrate on the loading limit of Au/C.

Silicon monoxide (SiO_x) has garnered considerable attention as an anode material owing to its high capacity. Nevertheless, its commercial viability is hampered by the low conductivity and inadequate cycling stability. In this study, a micrometer-scale silicon oxide/carbon composite (1000-SiOx/NC) was developed based on the porous and high electrical conductivity of pyrolyzed polydopamine (PDA) and the high-temperature disproportionation of SiO_x. Electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) analyses confirmed that the pyrolysis of polydopamine (PDA) not only improves electrode conductivity but also contributes to the formation of a stable solid electrolyte interface (SEI). Additionally, SiO_x undergoes disproportionation reactions during the pyrolysis of PDA, further the improves the cyclic stability of the composites. Consequently, the 1000-SiO_x/NC composite electrode exhibited an impressive specific capacity of 783.4 mAh·g⁻¹ after 500 cycles at 1 ​A ​g⁻¹, maintaining 80.1 ​% of its initial capacity. Additionally, at a high rate of 3 ​C, its capacity reached 607.3 mAh·g⁻¹ The synthesis approach is both straightforward and economical, offering a fresh avenue for the widespread commercial deployment of SiO_x.

Faradic-based capacitive deionization (FDI) has been widely acknowledged as one of the most promising desalination techniques to solve the freshwater crisis, yet was largely limited by heavily trailed development of its anode materials, which subsequently hindered its desalination performance in terms of both desalination capacity and stability. Herein, we developed a new type of anode material for FDI by coupling chloride-insertion FeOOH with carbon nanotubes (CNTs@FeOOH). The essence of this study lay in the composition of FeOOH with CNTs that could not only facilitate charge/electron transfer but also prevent structural aggregation. Consequently, the CNTs@FeOOH-based FDI system displays excellent desalination performance (desalination capacity: 50.36 mg g⁻¹; desalination rate: 0.41 mg g⁻¹ s⁻¹) with robust long-term stability (13.86 % reduction over 80 cycles), which could motivate the future development of other highly-efficient desalination systems.

CuO coating layers have attracted numerous attention due to its wide application in catalysis, batteries and other areas. However, the uncontrollable precipitation process of Cu²⁺ has made it challenging to form uniform CuO nanoshells. In this study, uniform CuO nanoshells were prepared through a delicate design. Namely, the uniform Cu²⁺-poly (m-phenylenediamine) (Cu-PmPD) nanoshells were constructed firstly, and then the organic parts in the Cu-PmPD were removed while uniform CuO nanoshells formed in the controllable calcination process. Applying this method to high-voltage cathode materials, the CuO was successfully coated on the LiNi_0·5Mn_1·5O_4, which greatly reduced the transition metal dissolution and improved the electrochemical performance in lithium-ion batteries.

Thermal energy storage is crucial in the context of achieving carbon neutrality. Phase change latent heat stands out among various thermal storage methods due to the high energy density of phase change materials (PCMs). PCMs possess unique characteristics such as tunable thermal storage or/and release processes, constant phase-transition temperatures, and changes in physical state. However, solid-liquid PCMs cannot be directly utilized due to the liquid leakage in their melted state. The encapsulation of PCM microcapsules (PCMMs) is essential for overcoming limitations and optimizing functionalities of the PCMs. Encapsulation strategies play a key role in considering factors like morphology, structure, physicochemical properties, and specific applications. Furthermore, PCMMs can expand their potential applications by incorporating functional nano-materials within their shells or introducing specific components into their cores during the synthesis process. This review examines various encapsulation strategies for PCMMs, including physical, physicochemical, and chemical methods. Various applications of PCMMs are summarized and analyzed with regards to the characteristics of PCMs in thermal storage, temperature control, and state transformation. Furthermore, the reinforcement strategies or/and design considerations of PCMMs are crucial for meeting specific requirements, such as conventional latent heat storage, thermal protection, and thermal-triggered intelligent materials. Finally, it discusses current challenges, proposed solutions, and future research directions in the field of PCMMs, particularly Janus particle modified PCMMs.

Pt-based catalysts are often used in a proton exchange membrane fuel cell due to their high activities to oxygen reduction and hydrogen oxidation reaction. However, these catalysts are easily poisoned by CO, resulting in a significant reduction of fuel cell performance. The use of CO-tolerant catalysts can effectively solve this problem. The CO poisoning mechanism and anti-poisoning strategies were briefly discussed in this article. It mainly focused on the research progress on CO-tolerant catalysts in three aspects: Pt alloy catalysts, metal oxide composite catalysts, and blocking layer covered catalysts. The advantages and limitations of various catalysts in recent years were also discussed. Creating a porous blocking layer covered on the surface of the catalyst can effectively enhance the CO-tolerance of the catalysts which could be a promising approach for developing anti-poison catalysts other than CO-tolerance. Finally, the prospects for future development of CO-tolerant fuel cell catalysts were described.

Transitional metal oxides are excellent candidates as heterogeneous catalysts for activating persulfate towards organics degradation. In this study, MnCo₂O₄ spinel was successfully prepared using a solvent-free molten method. The catalytic performance was systematically investigated and MnCo₂O₄ powder catalyst was successfully immobilized on polyurethane (PU) membrane through electrospinning to assess its application potential. The results showed that peroxymonosulfate (0.1 ​g ​L⁻¹) activated by MnCo₂O₄ (0.1 ​g ​L⁻¹) reached 99.92 ​% degradation in 10 ​min when treating 0.04 ​g ​L⁻¹ rhodamine B as target pollutant. The abundant oxygen vacancies formation, synergistic effect of Co and Mn ions and high electron transfer mobility are contributing to production of reactive oxygen species. Combining with quenching experiment and time-resolved EPR, the contribution of various active species was proposed, of which ¹O₂ exhibited the dominant role. The flowing reaction run by the MnCo₂O₄-PU membrane activating PMS exhibited universal degradation on different target pollutants.

Due to serious harm of triethylamine (TEA) to environmental safety and human health, it is significant to synthesize gas-sensitive materials with high performance for TEA detection. However, it is still a challenge to achieve high-sensitivity detection of TEA at low temperature for a sensor synthesized through an economical and efficient method. In this work, hollow-structured SnO₂ (HS-SnO₂) nanospheres have been fabricated by a facile, low-cost hydrothermal method in one step, which exhibit superior TEA-sensing properties, including not only ultrahigh response (127.75) for 100 ​ppm TEA, good selectivity, but also fast response and recovery time (17/28 ​s), low detection threshold (1 ​ppm) and robust stability at a relatively low optimum operational temperature of 225 ​°C. The excellent gas-sensitizing performances are ascribed to porous hollow structures with rich oxygen vacancies that provide abundant active sites for raising O₂ adsorption and reaction of TEA and oxygen species. This work offers an effective and economical strategy for fabricating high-performance TEA sensors for industrial applications.