RSC sustainability最新文献

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The development of sustainable catalytic methods is a crucial tool for advancing green chemistry and reducing its associated environmental impact. In this study, we present an eco-friendly approach for reducing azido and nitro compounds to their corresponding amines using a heterogeneous nickel-based catalyst supported on sulfonated biochar derived from pine needle (PiNe) valorisation. The system developed, in combination with the use of NaBH₄ as a safer reducing agent in water, enables efficient transformations under mild reaction conditions, yielding excellent results. The process also incorporates a green work-up procedure that employs bio-based, non-toxic solvents, such as 2-MeTHF, to aid in product isolation and catalyst recovery, thereby significantly reducing waste generation. Moreover, recycling studies demonstrate that Ni(B)/PiNe retains its catalytic efficiency for over five consecutive cycles. This work highlights the potential of biomass-derived materials in sustainable catalysis, demonstrating that green alternatives can be as effective as traditional methods while providing a protocol that aligns with the growing demand for environmentally friendly chemistry.

This study investigates the synthesis of LaMnO₃–CeO₂ composites with varying CeO₂ contents ((100 − x)% LaMnO₃–x% CeO₂; x = 0, 10, 30, 50, 100 wt%) via an autocombustion method to elucidate their synergistic electrochemical properties. X-ray diffraction (XRD) confirmed the presence of both LaMnO₃ (LMO) and CeO₂ phases in the anticipated stoichiometric ratios. Nitrogen adsorption–desorption isotherms revealed a mesoporous structure, with the LMO–CeO₂ (70 : 30) composite exhibiting the highest specific surface area of 14.32 m² g⁻¹, as determined by the Brunauer–Emmett–Teller (BET) method. X-ray photoelectron spectroscopy (XPS) provided insights into the ion valences and chemical composition of the composites. Electrochemical performance was evaluated in a 1 M KOH aqueous electrolyte using a three-electrode configuration. The LMO–CeO₂ (70 : 30) composite demonstrated superior performance, achieving a specific capacitance of 830.3 F g⁻¹ at a scan rate of 1 mV s⁻¹ and 637.6 F g⁻¹ at a current density of 1 A g⁻¹, corresponding to an energy density of 31.9 Wh kg⁻¹ at a power density of 357.5 W kg⁻¹. These results underscore the synergistic enhancement of electrochemical properties through the integration of LaMnO₃ and CeO₂, offering significant potential for the development of high-performance materials for energy storage applications.

A graphical abstract is available for this content

A graphical abstract is available for this content

A graphical abstract is available for this content

Due to rapid urbanization, industrial growth, and rising living standards, the intensification of global water pollution has become a pressing environmental and public health challenge. Effective and sustainable treatment technologies are urgently needed to mitigate these threats. Adsorption is a well-known, effective and sustainable approach because it is simple to operate, cost-effective, and highly efficient. In this context, porous materials derived from natural biopolymers have gained prominence as super-adsorbents for wastewater treatment due to their renewable origin, biodegradability and environmental compatibility. Biopolymers such as cellulose, chitosan, alginate, starch, and gelatin are often functionalized with electron-rich atoms such as nitrogen (N), oxygen (O), sulfur (S), metals, or fillers. These biopolymers exhibit a high affinity for a broad range of pollutants via mechanisms such as ion exchange, hydrogen bonding, and surface complexation. Recent advances in hybrid composites have enhanced the mechanical stability, adsorption capacity, and reusability of these materials, enabling them to achieve pollutant removal efficiencies of up to 99%. This review provides an extensive overview of the modification strategies, adsorption mechanisms, and performance metrics of biopolymer-based porous adsorbents.

The common issue of water contamination by pharmaceuticals are increasingly recognised as emerging contaminants in water as they pose significant environmental and health risks, necessitating innovative and sustainable approaches to water treatment. Activated biochar represents an effective solution for the removal of pharmaceuticals from water. Here, the focus was on the valorisation of Rhododendron ponticum, an invasive plant species in Ireland, into high-surface-area activated biochar through thermo-chemical treatments. In this work, phosphoric acid (H₃PO₄) was used for activation at two different temperatures (550 and 650 °C), which resulted in activated biochars that exhibited excellent adsorption properties with surface area of 876.3 and 869.2 m² g⁻¹ when treated at 550 and 650 °C, respectively. Structural and composition properties of the produced biochars were investigated by elemental CHNS (carbon, hydrogen, nitrogen, and sulphur) composition analysis, moisture content, fixed carbon, ash, and volatile matter. Acetylsalicylic acid (ASA), commonly referred to as aspirin, was used as a model pharmaceutical compound, and its removal from water was significantly enhanced by the activation process. The inactivated biochar showed the lowest ASA adsorption (113 mg g⁻¹), whereas the activated biochar exhibited much higher adsorption levels (267–296 mg g⁻¹). These results demonstrate that the biochar produced here is highly effective for the removal of aspirin from water. By converting problematic invasive biomass into a valuable resource, this work contributes to addressing environmental concerns associated with both invasive species and water pollution by developing eco-friendly adsorbent materials for removing emerging pharmaceutical contaminants from water.

Li ion battery (LIB) waste is an emerging environmental issue. Here we show that a typical LIB cathode material such as nickel manganese cobalt (NMC) oxide can be recovered and used directly as an electrocatalyst for the oxygen evolution reaction (OER). However, the impact of battery history indicates some decrease in OER performance.

Environmental contamination due to toxic chemicals, heavy metals, and organic pollutants poses a significant threat to public health and ecosystems. Traditional methods for detecting and removing these contaminants often face limitations in sensitivity, selectivity, and efficiency. Among the different methods, electrochemical methods have taken the front seat due to various advantages over other methods. Magnetic sensors, particularly those based on magnetically recoverable nanocomposites, offer unique advantages such as high surface area, catalytic properties, and ease of separation. Integrating electrochemical techniques with these sensors allows for precise detection and efficient remediation processes. This review focuses on the advancement of magnetic sensors for the electrochemical detection and remediation of environmental contaminants. Herein, we explore recent developments in sensor design, focusing on functional materials such as magnetic nanoparticles, carbon-based materials, and conducting polymers. Various electrochemical detection methods, including amperometry, voltammetry, and impedance spectroscopy, are discussed in terms of their performance metrics, such as sensitivity, selectivity, and detection limits. Beyond detection, this review demonstrates the potential of magnetic sensors in contaminant remediation, specifically through adsorption, photocatalysis, and electrochemical degradation. Furthermore, we provide a critical assessment of the field's current challenges, including sensor stability, scalability for real-world deployment, and the development of cost-effective, sustainable solutions. Finally, this review outlines the promising prospects for this technology, underscoring the expanding role of electrochemical magnetic sensors as vital instruments in addressing environmental pollution.