Advanced Sustainable Systems最新文献

Photocatalysis technology of g-C₃N₄ is of great value in wastewater treatment, thus calling for developing a concise and high-efficiency method to improve its photocatalytic efficiency. Here, a novel photocatalyst consisting of tourmaline particles (TPs) and graphitic carbon nitride (g-C₃N₄) is prepared by a step calcining method with enhanced photocatalytic performance. The self-polarized electric field of TPs attracts the photogenerated electrons generated by the catalyst and delays the recombination rate of electron-hole pairs, for which reason the prepared photocatalyst exhibits a wider spectral response and stronger photocatalytic activity. The mechanism analysis exhibits that the reactive substances including h⁺, ·OH, ¹O₂, and ·O₂⁻ generated by TPs/g-C₃N₄ effectively eliminate the contaminant during photocatalysis. The degradation efficiency of Rhodamine B (RhB) of g-C₃N₄-0.5% TPs is increased from 88.47% to 97.76% after 30 min illumination compared with pure g-C₃N₄. Furthermore, to facilitate catalyst recycling and reuse, a photocatalytic lignocellulose membrane is prepared. After five cycles, the degradation efficiency of the membrane decreases from 97.89% to 95.54%, still maintaining 97.60%. This study has constructed an innovative tourmaline/g-C₃N₄ photocatalyst and recyclable photocatalytic lignocellulose membrane with enhanced pollutant degradation properties by introducing naturally polarized minerals, providing a new approach for efficient water treatment.

Addressing the challenges of energy storage liquid leakage and long-term stability in energy storage is crucial for achieving sustainable energy efficiency. In this study, polymethyl methacrylate (PMMA) is innovatively employed as an encapsulation film on the surface of the wood-based phase change material, resulting in a recyclable wood-based composite energy storage material (PPW). A novel energy storage liquid (PCMs) composed of lauric acid (LA), capric acid (CA), and polyethylene glycol (PEG) is immersed in the pretreated porous wood frame through vacuum impregnation. The PCMs imparted a phase change temperature of 21.0 °C, which is close to human comfort levels, and a high energy storage efficiency of 31.6 J g⁻¹ to the PPW. Additionally, the PCMs provided the PPW with a photothermal conversion efficiency of 29.3%. Even after 200 freeze-thaw cycles, the energy storage properties of the PPW remained nearly unchanged. Therefore, utilizing PMMA as an effective encapsulation material is a viable approach to prevent leakage of the phase change solution and enhance the recyclability of the PPW. Furthermore, the transparency of PMMA preserves the natural appearance of the wood, thereby broadening the application potential of PPW in residential buildings, thermal energy storage, and solar thermal conversion systems.

Over the past few decades, the demand for lithium resources has increased significantly with the rapid development and extensive application of lithium-ion batteries. Extracting lithium from salt-lake brine is of significance because of its abundance in brines. Common methods for directly extracting lithium from salt lakes include precipitation, electrodialysis, and photothermal evaporation. Among these methods, lithium extraction using photothermal evaporation is considered an efficient and clean approach to addressing lithium shortages. In recent years, a lot of progress is made regarding lithium extraction with photothermal evaporation, so it is urgent to review the mechanistic basis and application of lithium extraction with photothermal evaporation. In this review, first, the mechanism of lithium extraction with photothermal evaporation is fully summarized, involving membrane separation, lithium-ion sieves, and separated crystallization. Second, a series of strategies for designing various evaporators with highly efficient lithium adsorption characteristics based on photothermal materials are further discussed in detail. Finally, recommendations and perspectives on the larger-scale development of lithium adsorbents by photothermal evaporation are proposed. Overall, this review not only offers in-depth insight into lithium extraction from brines with low Li⁺ concentration, but also inspires the development and design of next-generation lithium extraction evaporators with unprecedented properties.

Concern over the harmful impacts of pollutants on human health and the environment has increased in recent decades due to their widespread presence in water resources. These pollutants include pesticides, poisonous textile dyes, and micropollutants. It is essential to remove these pollutants from wastewater to enhance the quality of water for industrial usage. Because of externally hydrophilic and internally hydrophobic qualities, cyclodextrin and its derivatives have shown great promise as adsorbents for the treatment of wastewater. While cyclodextrins cannot be used as adsorbents on their own due to their water solubility, they can be efficiently polymerized with different types of cross-linkers to increase their stability and effectiveness. This review article examines chemically crosslinked materials based on cyclodextrin and its derivatives, utilizing various cross-linkers such as epichlorohydrin, glutaraldehyde, citric acid, N,N′-methylene bisacrylamide and maleic anhydride. These materials are evaluated for their effectiveness in adsorbing textile dyes, micropollutants, pharmaceuticals, and pesticides from wastewater. Additionally, this article provides a detailed explanation of adsorption kinetics, thermodynamics, and kinetic isotherms for the removal of contaminants. It also discusses the mechanism of contaminant adsorption, and reusability of adsorbents. Finally, this study delves into the challenges and exciting future prospects of CD-based adsorbents, highlighting their potential to revolutionize wastewater treatment.

Triboelectric nanogenerators (TENGs) represent an emerging technology that converts mechanical energy into electrical energy. Nonetheless, the most efficient TENGs are based on synthetic plastics or chemically treated materials. This study demonstrates a chemical-free, natural wood-based TENG with performance comparable to chemically treated wood-TENGs. The natural wood is paired with different polymers as an opposite layers in contact-separation mode, using various electrodes. The pristine wood-polytetrafluoroethylene (PW: PTFE) TENG device with a large area of 3 × 3 cm² exhibits a high open circuit voltage of 110 V, a short-circuit current of 0.72 µA, and generates charge of 23.6 ± 0.3 nC. Finally, to illustrate the viability of PW: PTFE triboelectric devices for practical applications, a prototype with a 20 × 18 cm² active area is discreetly inserted beneath a carpet to harness the energy generated by individuals walking or running across its surface. The cyclic nature of human motion ensures a sustained regimen of contact and separation, thereby yielding a consistent output of voltage and current, with a maximum open circuit voltage of 110 V, a short-circuit current of 193 µA, and a charge of 3.5 µC. These findings suggest that pristine wood is a promising material for low-cost and environmentally friendly TENGs.

The urgency to achieve carbon neutrality underlines the importance of shifting from carbon-based fossils to renewable resources. Bio-based polyethylene (bio-PE) is a key component of this transition, which is obtained from natural and renewable sources such as sugarcane. The environmental impact of bio-PE and fossil-based PE production is compared building ad-hoc sustainability indicators while exploring environmental, social, economic, and energetic aspects to provide a comprehensive evaluation. This methodology involves analyzing the entire lifecycle of both processes for polyethylene production, from extraction/harvesting to post-disposal actions, such as mechanical recycling or incineration. The main goal is to represent numerous sustainability indicators on a radar diagram, thus comparing process scores of sustainability. Bio-PE production has significantly higher scores than fossil carbon PE in terms of global warming potential (from cradle-to-gate), safety, and contribution to ozone depletion. Additionally, bio-PE offers a quite better scenario in terms of mass input and energy operating costs. On one side, bio-PE exhibits similar potential of eutrophication and acidification; on the other side, it also guarantees almost same potential revenues. This can address the choice to the most sustainable post-disposal method, that regards the mechanical separation and re-introduction of end-of-life PE into the manufacturing process.

The photocatalytic oxidation of glycerol into formic acid (FA) is reported employing a 9,10-anthraquinone-2,6-disulphonate disodium salt (AQDS) photocatalyst. The system operates in water, in the absence of additives, using O₂ as the oxidant and irradiating with blue light (λ = 415 nm). In 22 h, conversion of glycerol up to 79% leads to 30% yield of FA (turnover number of 15 for AQDS), with 79% selectivity among the products in solution and a quantum yield of 1.2%. The oxidation of glycerol is coupled to the reduction of oxygen to hydrogen peroxide (up to 16±5 mm), a high-added value photosynthetic product. A mechanistic investigation combining electron paramagnetic resonance (EPR) spectroscopy, transient absorption spectroscopy (TAS), and time-dependent density-functional theory (TD-DFT) calculations reveals a photoinduced hydrogen atom abstraction involving the triplet excited state ^3*AQDS and the glycerol substrate (k = 1.02(±0.03)×10⁷ m⁻¹·s⁻¹, H/D kinetic isotope effect = 2.00±0.16). The resulting ketyl radical of AQDS follows fast deprotonation to the radical anion AQDS^•–, that further reacts with oxygen (k = 1.2×10⁸ m⁻¹·s⁻¹), ultimately leading to the production of H₂O₂.

Flexible and printed supercapacitors (SCs) have emerged as reliable power sources for wearable and portable electronics. However, developing these SCs as sustainable and eco-benign, with high electrochemical performance, remains a challenge. Herein, scalable fabrication of SCs is demonstrated by formulating an activated carbon (AC) printable ink for the direct ink writing (DIW) of SCs. A water-based ink is prepared using a bio-degradable cellulose-based, sodium carboxymethylcellulose (Na CMC), binder replacing the typically used fluorinated binders, which are not environmentally friendly. Na CMC provides a stable ink dispersion with added mechanical and chemical stability to the printed SCs. The AC-Na CMC electrode produced 127.8 mF cm⁻² of specific capacitance. This AC-Na CMC ink is used to develop fully printed film-SCs and micro-SCs (m-SCs). The m-SC is fabricated with a printing resolution of 150 µm on photo paper. Using DIW enables scalable production, which is demonstrated by printing an array of m-SCs to power a micro-LED. The printed m-SC also demonstrates high mechanical flexibility, retaining 89.6% of its original capacitance at a bending angle of 90⁰. Na CMC as binder and photopaper as the substrate results in the production of biodegradable SCs extending their applicability to the field of transient electronics.

The development of low-cost, readily scalable catalytic systems for green hydrogen production is crucial for diverse research and industrial applications. This work demonstrates the facile coupling of carbon/NiFe-layered double hydroxide (LDH) onto flexible polyethylene terephthalate (PET) substrates deposited by blade coating and spray coating techniques. These low-temperature solution processes enable high-throughput electrode fabrication. The resulting carbon electrode exhibits sheet resistance of 25 Ω sq⁻¹, comparable to other state-of-the-art works, and displays excellent adhesion to the substrate and catalyst layer, thereby ensuring system stability. Remarkably, the developed electrode exhibits high catalytic activity for the oxygen evolution reaction (OER), achieving an overpotential of 215.9 and 267.4 mV at 10 mA cm⁻² in rigid and flexible substrates respectively, and maintaining its performance even at 10 mA cm⁻² for 24 h. This work highlights the potential of this methodology for producing readily transportable, flexible electrocatalytic systems with exceptional performance and minimal surface treatment of the substrate. Additionally, the use of low-cost, readily recyclable PET plastic aligns with the principles of circular economy, promoting the integration of this platform into both research and industrial environments.

In exploring the potential of Li₂MnSiO₄ as a cathode material for lithium-ion batteries (LIBs), the key challenges often involve enhancing electronic conductivity and lithium-ion diffusion rates. To address these issues, this paper proposes the combination of solid-state doping and a two-step calcination process to successfully prepare the Li₂Mn_1−xNi_xSiO₄ series of cathode materials, where Ni substitutes Mn at different doping amounts (x = 0, 0.02, 0.04, 0.06, 0.08). The use of chemically equivalent Ni²⁺ ions to replace Mn²⁺ ions is an effective method. Since the ionic radius of Ni²⁺ is smaller than that of Mn²⁺, this substitution can create more voids in the lattice structure. These increased voids provide smoother channels for the transport of electrons and lithium ions, thereby improving the material's electrical conductivity. At a Ni doping amount of 0.06, the material exhibits optimal electrochemical performance, achieving a discharge capacity of 155 mAh g⁻¹ at 0.1 C, significantly superior to undoped lithium manganese silicate. The doping of Mn sites with Ni significantly improves the conductivity and lithium-ion diffusion capabilities of Li₂MnSiO₄, revealing the tremendous potential of doping strategies in optimizing the performance of LIBs cathode materials.