ACS Sustainable Chemistry & Engineering最新文献

Understanding and controlling the elementary steps in catalytic processes during electrochemical reactions are crucial for advancing sustainable energy technologies. Herein, a promising concept of designing both elementary steps (water adsorption/dissociation and adsorbed hydrogen intermediate desorption) simultaneously is proposed for a robust hydrogen evolution reaction on Ru/Ni–P@Cu. The customized structure affords superb alkaline/neutral HER activity regarding reduced overpotential of 15/26 mV at 10 mA cm^–2. Notably, the alkaline/neutral HER mass activity (0.66/0.28 A mg^–1) and price activity (45.66/19.34 A dollar^–1) of Ru/Ni–P@Cu are 11.8/12.2 and 25.7/26.9 times higher than those of Pt/C, respectively. Experimental results and computational analyses reveal that the accessible Ru–Ni–P moieties on the interface confers the desired electronic structure, thereby promoting first elementary reaction of H₂O adsorption/dissociation, and simultaneously accelerating second elementary reaction of H* intermediate desorption via a hydrogen spillover. This work affords a transformative paradigm for elevating multistep catalytic reaction kinetics and paves the way for synergistic advancements in catalyst performance and cost-effectiveness.

To alleviate the resource shortage and environmental pollution, utilizing abundant solar energy effectively is a great challenge. In this article, a solar-thermal conversion material, Fe₂O₃-rGO, is integrated into the matrix of recyclable solid–solid phase change materials (RSSPCMs) to prepare solar-thermal conversion phase change materials, termed Fe₂O₃-rGO@RSSPCMs. The designed Fe₂O₃-rGO@RSSPCMs dexterously combine the solar-thermal conversion capability of Fe₂O₃-rGO with the thermal energy storage capability of RSSPCMs. Fe₂O₃-rGO@RSSPCMs exhibit a high latent heat of melting, reaching up to 108.58 J·g^–1, and demonstrate significant thermal storage capacity, along with excellent solar-thermal conversion efficiency. Notably, the introduction of Fe₂O₃-rGO into the molecular structure, activated by simulated sunlight, endows Fe₂O₃-rGO@RSSPCMs with remarkable self-healing properties and recyclability. Broken Fe₂O₃-rGO@RSSPCMs can be healed within 480 s under simulated sunlight irradiation (300 mW·cm^–2). Crucially, the structure, phase change behavior, and thermal stability of Fe₂O₃-rGO@RSSPCMs remain largely unchanged, even after multiple cycles. The design of Fe₂O₃-rGO@RSSPCMs is of considerable significance for achieving efficient solar energy utilization and promoting environmental protection.

Synthetic routes to sustainable aviation fuels are needed to mitigate the environmental impacts of the aviation sector. Among several emerging methods, the use of light-driven reactions benefits from milder conditions and the possibility of using sunlight to directly irradiate reactants or, alternatively, to power LEDs with a high and constant light intensity. Dinaphthylketone-photosensitized dimerization of isoprene can afford C₁₀ cycloalkenes that, after hydrogenation, meet the required properties for jet fuels (strongly resembling Jet-A). Isoprene can be photobiologically produced by metabolically engineered cyanobacteria from the conversion of CO₂ and water by utilizing solar light, contributing to a carbon-neutral process. The scale-up of such a combined photobiological–photochemical route is essential to bring it closer to the commercial level. Herein, we present the optimization and scale-up of the photosensitized dimerization of isoprene. By designing different reactor setups, flow versus no-flow conditions, and LED lamps (λ_max = 365 nm) versus sunlight as the light source, we reached a 2.6 L scale able to produce 61 mL of isoprene dimers per hour, which represents a 14-fold higher productivity compared to our previous results at a smaller scale. We also demonstrated a continuous feed process that converted isoprene into dimers with a 95% yield under LED irradiation. These advancements highlight the potential of light-driven processes to contribute to the energy transition and production of sustainable aviation fuels, making them more viable for commercial use and significantly reducing the environmental impact of the aviation sector.

We develop the multiliter-scale photodimerization of isoprene, a critical step of the combined photobiological–photochemical route to sustainable aviation fuels.

Carbon supports are important for the improved utilization of Pt nanoparticles (NPs), pore formation, and increased electrical conductivity in polymer electrolyte membrane fuel cells. This study uses electron-beam irradiation–reduction, which is a reductant-free catalyst-synthesis method with a fast synthesis time that is easy to scale up for mass production, to synthesize highly loaded and well-dispersed catalysts with 60 wt % of Pt NPs. The supports are prepared as commercial furnace black (EC-300J), acetylene black (Vinatech carbon black; VINA), and mesoporous carbon (MH18). In a half-cell, Pt/VINA displayed outstanding overall electrochemical performance; in particular, its electrochemical surface area (ECSA) has an average value of ∼24.6% higher than that of either of the other two catalysts. In catalyst-durability tests, the change in half-potential at 0.9 V_RHE is lower for Pt/VINA (−17.5%) than for either Pt/EC-300J (−25.2%) or Pt/MH18 (−33.9%). Similar results are obtained in single-cell catalyst-durability tests. The durability of the carbon support, evaluated in a single-cell test, shows that Pt/EC-300J exhibits the largest reduction in ECSA (−40.1%), followed by Pt/VINA (−28.9%) and Pt/MH18 (−26.2%). The electrode thickness of the highly crystalline Pt/VINA decreases by only −52.4%, while those of the Pt/EC-300J and Pt/MH18 electrodes are reduced by −66.1 and −60.9%, respectively. Interestingly, Pt/MH18 initially performed poorly due to the bulky carbon supports with narrow pore sizes, which resulted in agglomeration of the catalyst. After the support-durability test, however, the structure of this electrode remained well-maintained and exhibited excellent performance.

In this study, we introduce the chemical synthesis and kilogram-scale production of the novel monomer 4-((5-(hydroxymethyl)furan-2-yl)-methoxy)-4-oxobutanoic acid (HFBA), which is based on the biobased platform chemicals 5-hydroxymethyl-2-furfural (5-HMF) and succinic anhydride as starting materials. The synthesis process involves an initial straightforward ring-opening reaction of succinic anhydride with the hydroxy moiety of 5-HMF, yielding the adduct 4-((5-formylfuran-2-yl)-methoxy)-4-oxobutanoic acid (FFBA) in quantitative yield. The aldehyde functionality of FFBA is then selectively reduced under formation of the desired novel hydroxy acid monomer HFBA. The scalability of this efficient two-step process was successfully demonstrated already on a 1 kg scale, with an overall yield exceeding 99%. Furthermore, this new monomer possessing bifunctional hydroxy acid properties can be readily polymerized to form the fully biobased polyester poly(2,5-furandimethylenesuccinate) (PFMS). The resulting biobased polyester exhibits a glass transition temperature of 50 °C and a melting temperature of 180 °C. At 230 °C, polymer decomposition occurs, leading to the release of pure succinic acid. This decomposition can also contribute to a future strategy for recovery of the succinic acid monomer and thus to a chemical recycling strategy. It is further noteworthy that the polymer demonstrates strong adhesive properties when being applied as glue to surfaces from different material origin such as plastics, wood, or metal, surpassing even commercially available nonbiobased adhesives. HFBA has been readily polymerized to form the biobased polyester poly(2,5-furandimethylenesuccinate) (PFMS), which was characterized comprehensively and demonstrated strong adhesive properties.

Antioxidants found in olive leaves are high-added-value compounds for the pharmaceutical and food industries. This work aims to develop an efficient extraction process to recover such bioactive compounds using green, novel, and designable supramolecular solvents (SUPRAS). The supramolecular solvent/equilibrium solution (SUPRAS/EqS) systems were formed by ethanol, water, and five different amphiphiles: two organic acids (octanoic acid and decanoic acid) and three natural eutectic solvents (NAES) (octanoic acid: decanoic acid [1:1], menthol: octanoic acid [1:1], menthol: decanoic acid [1:1]). The SUPRAS/EqS systems were characterized in terms of the chemical compositions of the equilibrium phases, polarity, phase ratios, and phase diagrams of the ternary systems. Moreover, the unique microstructure of the proposed SUPRAS was demonstrated by using Scanning Electron Microscopy (SEM). Afterward, the extraction of polyphenolic antioxidants using SUPRAS/EqS was evaluated along with pure NAES, water, and ethanolic solutions for comparative purposes. The octanoic acid-based SUPRAS/EqS system achieved the highest extracted polyphenol content among all of the solvents tested. The extraction process was optimized by considering the SUPRAS/EqS composition, the SUPRAS/EqS ratio, the extraction time, the extraction method, and the solid–liquid ratio. The highest concentration of polyphenols in the extracts (68.67 mg polyphenols/g dry sample) was obtained with a SUPRAS/EqS composition of 20% (v/v) octanoic acid, 30% ethanol, and 50% water, at 40%/60% (v/v) SUPRAS/EqS ratio used in the extraction process, 1:15 sample:solvent ratio and 30 s of extraction time in vortex. Lastly, the stability of the polyphenolic extracts was evaluated under different storage conditions of temperature and light to assess the antioxidant degradation over time.