Industrial Chemistry & Materials最新文献

The membrane electrode assembly (MEA) plays a crucial role in the functionality of proton exchange membrane fuel cells (PEMFCs). The channels present within the catalyst layer of MEAs exhibit a disordered configuration, which consequently give rise to low efficiency in mass transportation. In order to enhance the mass transfer performance and the corrosion resistance of the catalyst layer, this paper developed a double-side ordered MEA based on TiN nanorod arrays. We synthesized TiN nanorod arrays on the ITO surface by a seed-assisted hydrothermal reaction and nitriding treatment, and coated the catalyst uniformly on the TiN support by ultrasonic spraying. Then the double-side ordered MEA was fabricated by transfer printing, and achieved a peak power of 678.30 mW cm⁻² with a cathode platinum loading of 0.2 mg cm⁻² at 80 °C and anode saturated humidity. After 200 hours of accelerated stress test (AST) at 90 °C and 30/30% relative humidity, the peak performance only dropped by 4.8%. These results provide substantial evidence for the effectiveness of our developed double-side ordered MEA which can mitigate catalyst polarization corrosion. Thus, this study reveals the immense potential of the TiN nanorod array-based double-side ordered MEA in advancing the development of efficient and stable MEAs.

Keywords: PEMFC; Preparation of MEA; Ordered MEA; TiN nanorod array; Catalyst carrier.

In the research described in this paper, the uses of the urea/thiourea complexation approach were employed to enhance the octane number of FCC gasoline by extracting n-alkanes. It was observed that adding thiourea improved the removal of the n-alkanes from gasoline, and matching results were obtained from experiments using model samples. Molecular dynamics simulation revealed that the stability of urea complexes increased as the carbon number of the n-alkanes was raised, whereas lighter n-alkane molecules exhibited a lower propensity for complex formation with urea. This finding is in agreement with the results of the DSC measurement at the decomposition temperature. Furthermore, infrared spectrum analysis, XRD characterization, and reaction heat measurements indicated that although thiourea was introduced into the reaction system, it did not actively participate in the complexation reaction. In summary, the introduction of thiourea resulted in an increased solubility of urea in an ethanol solution and enhanced the reaction heat, suggesting its beneficial role in promoting urea complex formation and facilitating n-alkane removal from FCC gasoline.

Keywords: Urea; Thiourea; FCC gasoline; Thermoanalysis; Molecular dynamics.

Bio-oil is a major product from pyrolysis of biomass which serves as a carbon source to produce carbon material due to its high reactivity towards polymerization itself or cross-polymerization with other organic feedstocks. In this study, activation of polyaniline (PANI) mixed with wheat straw-derived bio-oil and K₂C₂O₄ at 800 °C was conducted, aiming to understand the effect of potential interactions of bio-oil with PANI on pore development of resulting activated carbon (AC). The results revealed cross-polymerization reactions between PANI and bio-oil during direct activation, which increased the yield of AC from 13.0% (calculated average) to 15.0%, the specific surface area from 1677.9 m² g⁻¹ (calculated average) to 1771.3 m² g⁻¹, and the percentage of micropores from 94.3% to 97.1%. In addition, pre-polymerization of PANI and bio-oil at 200 °C before activation was also conducted. Such pretreatment could increase the AC yield from 13.0% to 23.3%, but the specific surface area decreased to 1381.8 m² g⁻¹. The pre-polymerization formed the organics that were more resistant towards cracking/gasification, but introduced oxygen-rich functionalities. This made AC highly hydrophilic, rendering a much higher capability for adsorption of phenol despite the smaller specific surface area. Additionally, the AC with developed pore structures facilitated dispersion of nickel in Ni/AC and enhanced the catalytic activity for hydrogenation of o-chloronitrobenzene and vanillin.

Keywords: Polyaniline; Bio-oil; Activation; Activated carbon; Pre-polymerization; Adsorption.

Liquid-based materials have emerged as promising soft materials for bioelectronics due to their defect-free nature, conformability, robust mechanical properties, self-healing, conductivity, and stable interfaces. A liquid is infiltrated into a structuring material endowing the material with a liquid-like behavior. Liquid-based electronics with favorable features are being designed and engineered to meet requirements of practical applications. In this review, various types of liquid-based electronic materials and the recent progress on bioelectronics in multiple applications are summarized. Liquid-based electronic materials include ionic liquid hydrogel, nanomaterial-incorporated hydrogel, liquid metal, liquid-infused encapsulation, and liquid-based adhesive. These materials are demonstrated via electronic applications, including strain sensor, touch sensor, implantable stimulator, encapsulation, and adhesive as necessary components comprising electronics. Finally, the current challenges and future perspective of liquid-based electronics are discussed.

Keywords: Bioelectronics; Liquid metal; Soft electronics; Hydrogel electronics; Lubricant-infused.

An inhomogeneous catalyst surface leads to concentration gradients along this surface, which can generate diffusio-osmotic flows. The magnitude of this surface flow and the extent to which it impacts the catalytic conversion is numerically investigated and depends foremost on the reaction kinetics of the system and the surface-species interactions expressed via the diffusio-osmotic mobility. We present general scaling laws based on the reaction kinetics and interaction potential between chemical species and the catalytic surface, captured in a single parameter. We further investigate the optimal catalyst coverage in order to maximize the benefit of these surface flows.

Keywords: Diffusio-osmosis; Catalysis; Transport; Enhancement.

Antifouling liquid-infused surfaces have generated interest in multiple fields due to their diverse applications in industry and medicine. In nearly all reports to date, the liquid component consists of only one chemical species. However, unlike traditional solid surfaces, the unique nature of liquid surfaces holds the potential for synergistic and even adaptive functionality simply by including additional elements in the liquid coating. In this work, we explore the concept of multi-component liquid-infused systems, in which the coating liquid consists of a primary liquid and a secondary component or components that provide additional functionality. For ease of understanding, we categorize recently reported multi-component liquid-infused surfaces according to the size of the secondary components: molecular scale, in which the secondary components are molecules; nanoscale, in which they are nanoparticles or their equivalent; and microscale, in which the additional components are micrometer size or above. We present examples at each scale, showing how introducing a secondary element into the liquid can result in synergistic effects, such as maintaining a pristine surface while actively modifying the surrounding environment, which are difficult to achieve in other surface treatments. The review highlights the diversity of fabrication methods and provides perspectives on future research directions. Introducing secondary components into the liquid matrix of liquid-infused surfaces is a promising strategy with significant potential to create a new class of multifunctional materials.

Keywords: Active surfaces; Antimicrobial; Antifouling; Interfaces; Sensing surfaces.

The exothermic characteristic of the water-gas-shift (WGS) reaction, coupled with the thermodynamic constraints at elevated temperatures, has spurred a research inclination towards conducting the WGS reaction at reduced temperatures. Nonetheless, the challenge of achieving efficient mass transfer between gaseous CO and liquid H₂O at the photocatalytic interface under mild reaction conditions hinders the advancement of the photocatalytic WGS reaction. In this study, we introduce a gas–liquid–solid triphase photocatalytic WGS reaction system. This system facilitates swift transportation of gaseous CO to the photocatalyst's surface while ensuring a consistent water supply. Among various metal-loaded TiO₂ photocatalysts, Rh/TiO₂ nanoparticles positioned at the triphase interface demonstrated an impressive H₂ production rate of 27.60 mmol g⁻¹ h⁻¹. This rate is roughly 2 and 10 times greater than that observed in the liquid–solid and gas–solid diphase systems. Additionally, finite element simulations indicate that the concentrations of CO and H₂O at the gas–liquid–solid interface remain stable. This suggests that the triphase interface establishes a conducive microenvironment with sufficient CO and H₂O supply to the surface of photocatalysts. These insights offer a foundational approach to enhance the interfacial mass transfer of gaseous CO and liquid H₂O, thereby optimizing the photocatalytic WGS reaction's efficiency.

Keywords: Water-gas-shift; Photocatalysis; Triphase interface; Hydrogen evolution; TiO₂.

Micro-sized anode materials demonstrate greater potential for practical applications than nanomaterials in the aspects of volumetric energy density, coulombic efficiency, fabrication process, and cost. However, the huge volume changes of alloy anodes (up to ∼500%) during repeated charge/discharge has led to a series of challenging issues including pulverization of active material particles and delamination from current collectors, formation of thick and fragile solid-electrolyte interphase (SEI) and depletion of electrolytes, eventually leading to rapid cell degradation. Herein, we review recent progress of rational strategies to enable the use of microsized alloy anodes (Si, P, Sb, Sn, etc.) including electrolyte modulation, binder design and architecture engineering. We also provide perspectives on future directions and remaining challenges of microsized anodes towards practical applications.

Keywords: Volume change; Alloy; Anodes; Microsized; Alkali-ion; Batteries.

This work presents a theoretical investigation of carbon dioxide (CO₂) adsorption on MgH₂ and its reaction (chemisorption) with cobalt doped MgH₂. The focus of this study is the properties and mechanisms involved in CO₂ adsorption on clean MgH₂ surfaces and the role of Co in enhancing the adsorption process. Density functional theory (DFT) calculations were performed to examine different CO₂ adsorption sites on the MgH₂ surface along with the adsorption distances, binding energies, and geometric parameters. The results indicate that physical adsorption of CO₂ occurs on MgH₂ with similar adsorption energies at different adsorption sites. The coverage effect of CO₂ molecules on MgH₂ was also investigated, revealing an increased affinity of CO₂ with higher surface coverage. However, excessive coverage led to a decrease in adsorption efficiency due to competing surface adsorption and intermolecular interactions. The orientation of adsorbed CO₂ molecules shifted from parallel to quasi-perpendicular arrangements upon adsorption, with notable deformations observed at higher coverage, which gives a hint of CO₂ activation. Furthermore, the study explores the CO₂ adsorption capacity of MgH₂ in comparison to other materials reported in the literature, showcasing its medium to strong affinity for CO₂. Additionally, the effectiveness of a single Co atom and Co clusters as catalysts for CO₂ adsorption on MgH₂ was examined. Overall, this theoretical investigation provides insights into the CO₂ adsorption properties of MgH₂ and highlights the potential of Co catalysts to enhance the efficiency of the methanation process.

Keywords: DFT; CO₂ conversion; Cobalt catalyst; Charge transfer.

The electrocatalytic reduction of carbon dioxide (CO₂) is considered an effective strategy for mitigating the energy crisis and the greenhouse effect. Nickel is widely used in single-atom catalysts (SACs) owing to its special electronic structure. In this minireview, the basic principles of Ni SACs in the electrocatalytic reduction of CO₂ to CO are first described. Subsequently, Ni SACs are divided into three categories depending on different strategies used to improve properties. The synthesis, morphology, performance and theoretical calculations of the catalysts are also described. Finally, an overview of the existing challenges and perspectives of Ni SACs for CO₂ reduction is presented.

Keywords: CO₂ reduction; Electrocatalysis; Nickel single-atom catalysts.