Environmental Remediation Applications Research Articles

Fe/Ni bimetallic magnetic nano-alloy (INBMNA): An efficient heterogeneous catalyst for photo-Fenton-like degradation of phenol in aqueous environment

A lot of attention has been drawn to photo-Fenton-like catalysis among advanced oxidation processes for environmental remediation applications. Herein, we have successfully fabricated iron-nickel bimetallic magnetic nano-alloy (INBMNA) as an efficient heterogeneous photo-Fenton-like catalyst using the chemical reduction method and characterized by several analytical techniques. The characterization results show that the catalyst has a spherical shape with a mesoporous nature and contains a large specific surface area. The impact of various parameters was investigated and optimized to check the catalytic performance of INBMNAs and the found results showed that excellent photo-Fenton-like activity persisted under 6.0 pH conditions for the degradation of hazardous pollutant (phenol) under solar light exposure and microwave radiation power, respectively. Additionally, the exposed INBMNA/H2O2 system provided continuous redox cycles of Fe3+/Fe2+ and Ni2+/Ni0 pair in the Fenton-active species for stable operation. The photo-Fenton-like activity was also performed to check the effect of different inorganic anions which significantly hinder phenol reduction. Besides, the steady performance of the catalyst to remove phenol was performed in tap water and river water. Free radical trapping experiments were tested to know the role of important radicals in the photo-Fenton process. Moreover, the mechanism and possible degradation pathways of phenol were checked. By cyclic degradation experiments, the performance of the catalyst is stable and almost unchanged and can be reused several times. This study provides a promising INBMNA/H2O2 system, which encourages its widespread use in environmental remediation applications.

Polyaniline and Graphene Oxide or Reduced Graphene Oxide-Based Composites for Environmental Remediation Application

Polyaniline and Graphene Oxide or Reduced Graphene Oxide-Based Composites for Environmental Remediation Application

Valorization of Agriculture Residues into Value-Added Products: A Comprehensive Review of Recent Studies.

Global agricultural by-products usually go to waste, especially in developing countries where agricultural products are usually exported as raw products. Such waste streams, once converted to "value-added" products could be an additional source of revenue while simultaneously having positive impacts on the socio-economic well-being of local people. We highlight the utilization of thermochemical techniques to activate and convert agricultural waste streams such as rice and straw husk, coconut fiber, coffee wastes, and okara power wastes commonly found in the world into porous activated carbons and biofuels. Such activated carbons are suitable for various applications in environmental remediation, climate mitigation, energy storage, and conversions such as batteries and supercapacitors, in improving crop productivity and producing useful biofuels.

Molybdate-based Nanocrystalline Materials for Efficient Environmental Remediation and Electrochemical Energy Conversion Applications: An Update

Molybdate-based Nanocrystalline Materials for Efficient Environmental Remediation and Electrochemical Energy Conversion Applications: An Update

Heavy-Metal Ions Removal and Iodine Capture by Terpyridine Covalent Organic Frameworks.

Porous materials are excellent candidates for water remediation in environmental issues. However, it is still a key challenge to design efficient adsorbents for rapid water purification from various heavy metal ions-contaminated wastewater in one step. Here, two robust nitrogen-rich covalent organic frameworks (COFs) bearing terpyridine units on the pore walls by a "bottom-up" strategy are reported. Benefitting from the strong chelation interaction between the terpyridine units and various heavy metal ions, these two terpyridine COFs show excellent removal efficiency and capability for Pb2+, Hg2+, Cu2+, Ag+, Cd2+, Ni2+, and Cr3+ from water. These COFs are shown to remove such heavy metal ions with >90% of contents at one time after the aqueous metal ions mixture is passed through the COF filter. The nitrogen-rich features of the COFs also endow them with the capability of capturing iodine vapors, offering the terpyridine COFs the potential for environmental remediation applications.

Superparamagnetic hydrophilic molecularly imprinted nanoparticles for an efficient and selective removal of tetracycline from water

In this work, a novel superparamagnetic hydrophilic molecularly imprinted nanomaterial for the removal of tetracycline (TC) was synthesized utilizing magnetite (Fe3O4) as the magnetic core, TC as the template molecule, 3-aminopropyltriethoxysilane (APTES) as the functional monomer, and tetraethoxysilane (TEOS) as the cross-linker. Initially, Fe3O4 magnetic nanoparticles (MNP) coated with SiO2 (MNP@SiO2) were synthesized, followed by TC molecular imprinting on the nanoparticles. Initially, Fe3O4 MNP coated with SiO2 (MNP@SiO2) were synthesized, followed by TC molecular imprinting on the nanoparticles. The synthesis method for MNP@SiO2 was optimized, and DLS analysis of 10 replicates showed a nanoparticle size of 70.1 ± 5.8 nm, indicating high method reproducibility. The MNP@SiO2, as well as the imprinted (MNP@SiO2-MIP) and non-imprinted (MNP@SiO2–NIP) nanomaterials, were characterized by FTIR, TEM, VSM, XRD, DLS, Z potential, and BET analysis. The saturation magnetization (Ms) values were 43 emu/g for MNP@SiO2 and 32 emu/g for both MNP@SiO2-MIP and MNP@SiO2–NIP, confirming suitability for magnetic separation using external magnets. Batch binding experiments conducted in water and methanol assessed adsorption isotherms and binding kinetics, with data fitting the Langmuir isotherm model better than the Freundlich model. The developed MIP exhibited significant selectivity against other molecules with similar functional groups and size. In water, the adsorption capacity of the MNP@SiO2-MIP was 23 mg/g, with an imprinting factor of 2.2. Furthermore, the MIP demonstrated good regeneration performance. The material was tested on TC-spiked tap water samples, achieving 80.1 % TC removal with high reproducibility (3.2 %, n = 3). Combining hydrophilic superparamagnetic nanoparticles with molecular imprinting enhances their potential applications in environmental remediation, antibiotic purification, and drug delivery.

Synthesis and characterization of hierarchical Sr-doped ZnO hexagonal nanodisks as an efficient photocatalyst for the degradation of methylene blue dye under sunlight irradiation

This study presents the synthesis and comprehensive characterization of hierarchical hexagonal nanodisks of zinc oxide (ZnO) and strontium (Sr) doped ZnO, prepared via a hydrothermal method. The experimental synthesis procedure involved dissolving zinc nitrate in a water–ethanol mixture, followed by the addition of polyethylene glycol (PEG 200), sonication, and subsequent hydrothermal treatment. Different concentrations of Sr were introduced into the ZnO lattice to generate Sr-doped ZnO samples. Analysis of the obtained results revealed successful incorporation of Sr, evidenced by shifts in the X-ray diffraction (XRD) pattern and alterations in lattice parameters. Moreover, the Williamson-Hall plot indicated minimal strain and high structural stability in both pristine ZnO and Sr-doped ZnO. The morphology of the synthesized Sr-doped ZnO was confirmed through field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), revealing a hexagonal nano disk-shaped morphology akin to pristine ZnO. Elemental composition analysis conducted via X-ray photoelectron spectroscopy (XPS) further confirmed the presence of Sr in the doped ZnO samples. Evaluation of photocatalytic activity against methylene blue dye demonstrated superior performance of the 5 % Sr-doped ZnO catalyst, attributed to its increased surface area compared to pristine ZnO. Notably, the highest degradation rate constant (k) of 0.0389 min−1 was observed for the 5 % Sr-doped ZnO catalyst, emphasizing its efficacy in environmental remediation applications. This research underscores the potential of Sr-doped ZnO as a promising photocatalyst, offering stability, reusability, and effective utilization of UV and visible light for catalytic processes.

All-Aqueous Soft Milli-swimmers.

Microscale swimmers are attractive for targeted drug delivery, noninvasive microsurgery and environmental remediation at different length scales, among which, Marangoni-based swimmers have garnered considerable attention due to their independence of external energy supply. However, applications of most existing chemical swimmers are limited by complex fabrication, high cost, utilization of organic (or even toxic) solvents, poor motility performance, and lack of controllability. To address these challenges, we propose an approach for all-aqueous soft milli-swimmers that utilizes biodegradable hydrogels and biocompatible fuels. This innovative method achieves swimmer body generation and fuel loading in one step by simply dripping one aqueous solution into another, saving fabrication time and minimizing fuel loss during transfer. These all-aqueous soft milli-swimmers have rove beetle-like self-propulsion, which stores low-surface-energy compounds within their body for propulsion on liquid surfaces. Isotropic and anisotropic all-aqueous soft milli-swimmers are formed with precise control over their dimension, morphology, and movement velocity. Through their motion within engineered channels, intricate labyrinths, dynamic air-liquid interfaces, and collective self-assemblies, their remarkable adaptability in complex aqueous environments is demonstrated. Furthermore, the integration of functional nanoparticles endows these all-aqueous milli-swimmers with multifunctionality, expanding their applications in cargo transportation, sensing, and environmental remediation.

Methyl orange sorption on octadecylamine-modified iron oxide magnetic nanoparticles

This study investigates the sorption of 2-methyl orange dye onto octadecylamine-modified iron oxide magnetic nanoparticles (ODA-IONPs). The synthesized ODA-IONPs exhibit remarkable sorption capacity, reaching 800 mg/g at the nanoparticle concentrations ranging from 5 to 10 mg/g and pH of 2–8. The sorption process demonstrates rapid kinetics, achieving 90% of maximum sorption within 0.5 min. Thermodynamic analysis showed that sorption process is spontaneous and endothermic, as indicated by negative ΔG and positive ΔH values. The pseudo-second-order and Langmuir models best describe the sorption kinetics at 293 K (R² 0.99). Compared to other adsorbents, ODA-IONPs show superior MO removal capacity under a wider pH range. The influence of nanoparticle concentration, pH, and temperature on sorption efficiency is systematically explored, with optimal conditions identified at 10 mg/L ODA-IONPs and pH 6. Furthermore, the feasibility of nanoparticle reusability for sorption purposes is assessed. These findings underscore the potential of ODA-IONPs as efficient sorbents for wastewater treatment and environmental remediation applications.

Chitosan based Nanocomposites: Its Synthesis, Characterization and Applications in Various Fields: A Review

Nanocomposites: modern material are multiphase martial composed of one or many phases of less than 100 nm dimensions. Polymer –matrix nanocomposites are composed of polymer matrix reinforced with nanoscale fillers. Chitosan is the most abundant biopolymer after cellulose, extracted from chitin present in insect exoskeleton fungal cell wall, and crustaceans. Chitosan gains the attention of many researcher because of its unique properties like biodegradable, plant growth regulator, biocompatible, antimicrobial agent and nontoxic. Chitosan nanocomposites combine the benefits of chitosan with enhanced properties provided by nanoparticles making them versatile and high performing material. Chitosan nanocomposites has numerous application in industries, biomedical, food packaging, and environmental remediation. This review focuses on the Chitosan nanocomposites synthesis, their characterization and applications in various fields.

Structure and defect engineering synergistically boost Mo6+/Mo4+ circulation of Sv-MoS2 based photo-Fenton-like system for efficient levofloxacin degradation

The kinetics of redox couples based exclusively on peroxymonosulfate (PMS) are notably slow and inefficient. In this study, urchin-like Sv-MoS2 were in situ deposited onto defect-rich NBC-C3N5 surfaces using a hydrothermal method. The inherent defects in NBC-C3N5@Sv-MoS2 (NCM) along with sulfur vacancies (Sv) directionally inject electrons into Mo sites through a “stabilize-then-accelerate” strategy, culminating in the self-regeneration of Mo sites. Both experimental data and Density Functional Theory (DFT) calculations confirm that NCM effectively activates PMS, generating hydroxyl radicals (•OH) and sulfate radicals (SO4•-) for the degradation of Levofloxacin (LFX) under visible light. The presence of Sv-MoS2 notably extends the peroxy bond (O-O) length in PMS, enhancing electron flux and thereby facilitating superior radical generation compared to singlet oxygen (1O2). Furthermore, experimental assessments of reactors and stirring devices within the NCM system underscore its potential applications in water environmental remediation.

Novel green CQDs/ZnO binary photocatalyst synthesis for efficient visible light irradiation of organic dye degradation for environmental remediation

The advancement of effective and sustainable water treatment depends on the creation of a highly active and controllable photocatalyst. A suitable site for increasing the activity of such a photocatalyst is the heterojunction. Organic dyes have become a major source of concern in recent years because they are so common in wastewater. Heavy metals have a high permanence in wastewater and may be carcinogenic. Low-waste, high-performance technologies are needed to remove organic dyes and heavy metals from wastewater. To determine their structural, photochemical, and optical properties, Carbon Quantum Dots (CQDs) (made from Tamarindus indica shell waste), ZnO (from Ficus Benghalensis), and CQDs/ZnO photocatalysts were synthesised using green route techniques, followed by calcination. Malachite Green (MG) and Methylene Blue (MB) are effectively photo-degraded by the synthesised CQDs, ZnO, and Green CQDs/ZnO Binary Photocatalyst under the irradiation of naturally occurring solar light. The maximum photocatalytic activity for MG and MB within 60 min was shown by the Green CQDs/ZnO Binary Photocatalyst, with 100 % and 100 %, respectively. The reduced rate of electron-hole recombination causes effective photocatalytic activity. According to experiments with free radical entrapment, O2 and h+ play an important role in photodegradation. The study thus presents a fresh approach to the synthesis of highly effective binary photocatalysts for their application in environmental remediation.

Biomimetic green synthesis of ZnO nanoflowers using α-amylase: from antimicrobial to toxicological evaluation

Biologically mediated synthesis of nanomaterials has emerged as an ecologically benign and biocompatible approach. Our study explores enzymatic synthesis, utilizing α-amylase to synthesize ZnO nanoflowers (ZnO-NFs). X-ray diffraction and energy-dispersive X-ray spectroscopy revealed crystal structure and elemental composition. Dynamic light scattering analysis indicates that ZnO-NFs possess a size of 101 nm. Transmission electron microscopy showed a star-shaped morphology of ZnO-NFs with petal-like structures. ZnO-NFs exhibit potent photocatalytic properties, degrading 90% eosin, 87% methylene blue, and 81% reactive red dyes under UV light, with kinetics fitting the Langmuir–Hinshelwood pseudo-first-order rate law. The impact of pH and interfering substances on dye degradation was explored. ZnO-NFs display efficient bacteriocidal activity against different Gram-positive and negative strains, antibiofilm potential (especially with P. aeruginosa), and hemocompatibility up to 600 ppm, suggesting versatile potential in healthcare and environmental remediation applications.

Preparation of ternary BiVO4/g-C3N4/diatomite composites for enhanced photodegradation of rhodamine B and formaldehyde

Efficient ternary BiVO4/g-C3N4/diatomite (BCNDE) composites were prepared using a strategy combining in situ polymerisation and self-assembly. The photocatalytic degradation efficiencies of BCNDE composites for rhodamine B (RhB) and formaldehyde (CH2O) were investigated. Compared with BiVO4 (BVO), g-C3N4 (CN) and BiVO4/g-C3N4 (BCN), BCNDE showed better photocatalytic performance for RhB and CH2O degradation. Notably, the 20-BCNDE composite demonstrated superior photocatalytic performance, achieved 99 % degradation of RhB under visible light (λ > 400 nm) within 60 min and 81 % degradation of CH2O gas (0.16 mg·L−1) within 40 min. Incorporation of porous microdisc-shaped diatomite (DE) significantly mitigated the agglomeration of the BCNDE composites, as confirmed by scanning electron microscopy (SEM). This structural feature enhanced the separation and migration of photogenerated electron-hole pairs, as evidenced by photoluminescence (PL) spectroscopy and electrochemical impedance spectroscopy (EIS) analyses. Zeta potential analysis at pH 7 revealed a negatively charged surface with a zeta potential of −8.9 mV, facilitating the attraction of photogenerated holes and inhibiting electron-hole recombination. This effectively inhibited the recombination rate of photogenerated electron-hole pairs, thereby significantly improving the photocatalytic performance of the material. These mechanisms were critical in boosting the photocatalytic degradation activities for RhB and CH2O. This study highlights the potential of BCNDE composites for environmental remediation applications, offering a promising approach for the development of efficient mineral-based photocatalytic materials.

Optimization, kinetic analysis, and photocatalytic degradation of rhodamine B using manganese doped nanoscale nickel oxide nanoparticles

This work focuses on the synthesis and characterization of nanoscale nickel oxide (NiO) nanoparticles doped with manganese (Mn) utilizing the cost-effective co-precipitation technique. For extensive characterization, a range of analytical methods are used, such as photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet–visible (UV) spectroscopy, and Brunauer–Emmett–Teller (BET) surface area analysis. The findings demonstrate that the addition of Mn causes the synthesized nanoparticles' crystalline size to decrease, which narrows the band gap to 3.13 eV. Furthermore, compared to pure NiO (44.11 m2/g), the surface area of Mn-doped NiO increases to 178.87 m2/g. Also as compared to pure NiO the electron-hole recombination rate of % Mn-doped NiO has decreased and an increase in the defect is observed. The study of Mn-doped NiO nanoparticles' photocatalytic activity against Rhodamine B (Rh. B) demonstrates their improved efficiency under solar light irradiation, as evidenced by their degradation up to 97.57 %, which is higher than that of pure NiO (90.94 %) in 70 min. Numerous aspects are investigated, including pH, catalyst dosage, original dye concentration, and scavenger studies. Studies on regeneration show that 5 % Mn-doped NiO nanoparticles may be recycled effectively and steadily for up to five cycles. These results demonstrate how effective photocatalysts for environmental remediation applications may be made from Mn-doped NiO nanoparticles.

Fabrication of SrTiO3 anchored rGO/g-C3N4 photocatalyst for the removal of mixed dye from wastewater: dual photocatalytic mechanism

A metal-free combination of rGO/g-C3N4-coupled SrTiO3 (SRN) ternary nanocomposite prepared via a wet impregnation method for UV–Vis light photocatalytic applications. Various physicochemical properties of the samples were investigated by several spectroscopic techniques including X-ray diffraction (XRD), FT-IR, Raman, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FE-SEM-EDX), high-resolution transmission electron microscopy (HR-TEM), UV–Vis, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) surface area analysis. The data suggest agglomerated SRT nanoparticles are dispersed and distributed throughout the surface of the rGO sheets and GCN nanostructures. The photocatalytic performance of the SRN towards combined mixed dye and its degradation activities were evaluated towards the most common industrial effluents, Rhodamine B (RhB) and Methylene blue (MB), under UV–Vis light illumination. The results revealed that the degradation efficiency of the SRN photocatalyst shows excellent performance compared with that of the binary composition and the pure SrTiO3 (SRT) sample. The reaction rate constant for RhB was estimated to be 0.0039 min−1 and for MB to be 0.0316 min−1, which are 3.26 (RhB) and 4.21 (MB) times faster than the pure SRT sample. The enhanced degradation efficiency was attained not only by interfacial formation but also by the speedy transportation of electrons across the heterojunction. After 5 runs of the photocatalytic recylic process, the SRN photocatalyst exhibited ultimate stability without structural changes, and no noticeable degradation was observed. The outcomes of the ternary SRN nanocomposite manifest a dual photocatalytic scheme, the photocatalytic enrichment could be caused by the Z-scheme charge transfer process between GCN, SRT, and rGO nanocomposite, which helps effectual charge separation and keeps a high redox potential. From the results, SRN sample provides insight into the integration of an effective and potential photocatalyst for wastewater treatment toward real-time environmental remediation applications.

Magnetic Tunability via Control of Crystallinity and Size in Polycrystalline Iron Oxide Nanoparticles.

Iron oxide nanoparticles (IONPs) arewidely used for biomedical applications due to their unique magnetic properties and biocompatibility. However, the controlled synthesis of IONPs with tunable particle sizes and crystallite/grain sizes to achieve desired magnetic functionalitiesacross single-domain and multi-domain size ranges remains an important challenge. Here, a facile synthetic method is used to produceiron oxide nanospheres (IONSs) with controllable size and crystallinity for magnetic tunability. First, highly crystalline Fe3O4 IONSs (crystallite sizes above 24nm) having an averagediameter of 50 to 400nm are synthesized with enhanced ferrimagnetic properties. The magnetic properties of these highly crystalline IONSs are comparable to those of their nanocube counterparts, whichtypically possess superior magnetic properties. Second, the crystallite size can be widely tuned from 37 to 10nm while maintaining the overall particle diameter, thereby allowing precise manipulation from the ferrimagnetic to the superparamagnetic state. In addition, demonstrations of reaction scale-up and the proposed growth mechanism of the IONSs are presented. This study highlights the pivotal role of crystal size in controlling the magnetic properties of IONSs and offers a viable means to produce IONSs with magnetic properties desirable for wider applications in sensors, electronics, energy, environmental remediation, and biomedicine.

Illuminating the Power of V2O5 Nanoparticles: Efficient Photocatalytic Degradation of Organic Dyes under Visible Light.

This research explores the synthesis, characterization, and application of Vanadium Pentoxide nanoparticles (V2O5 NPs), focusing on their efficacy in the photocatalytic degradation of organic dyes under visible light. Utilizing a co-precipitation method, we synthesized V2O5 NPs characterized by an orthorhombic crystal structure with a consistent average particle size of 28nm. The optical properties of V2O5 NPs, including their band gap, were thoroughly investigated to understand their light absorption capabilities, which are crucial for photocatalytic activity. In our study, Methyl Violet (MV) dye was employed as a model organic pollutant to assess the photocatalytic performance of the nanoparticles. Under visible light irradiation, the V2O5 nanoparticles demonstrated an exceptional photocatalytic degradation efficiency, achieving up to 85% degradation of the MV dye within 100min. This high level of efficiency is attributed to the nanoparticles' ability to effectively absorb visible light and generate electron-hole pairs, thereby facilitating a robust degradation process. Further analysis revealed that the photocatalytic activity led to the generation of reactive oxygen species (ROS) such as superoxide and hydroxyl radicals, which are integral to the dye degradation mechanism. These ROS play a critical role in breaking down the dye molecules, significantly contributing to the overall effectiveness of the photocatalytic process. The results of this study highlight the potential of V2O5 nanoparticles as a sustainable and effective photocatalytic material for environmental remediation applications, particularly in the treatment of wastewater containing organic dyes. This research not only advances our understanding of the photocatalytic properties of V2O5 nanoparticles but also demonstrates their practical application in addressing environmental pollution through innovative and efficient degradation of hazardous substances.

Enhanced photocatalytic removal of Cr(VI) and Rhodamine B from water using plant-mediated CdS nanoparticles: Mechanistic insights and environmental applications

Photocatalytic remediation using semiconductor nanoparticles presents a promising approach for water purification. In this study, cadmium sulfide (CdS) nanoparticles were synthesized via a plant-mediated approach and evaluated for their efficacy in removing Cr(VI) and Rhodamine B contaminants from aqueous solutions under visible light irradiation. The CdS nanoparticles were characterized by X-ray diffraction (XRD), which confirmed the presence of the cubic phase with a crystallite size of 10 nm. UV–visible diffuse reflectance spectroscopy (DRS) indicated bandgap energy of 2.4 eV, facilitating visible light absorption. Photoluminescence (PL) spectroscopy revealed reduced recombination rates of photogenerated charge carriers, enhancing photocatalytic efficiency. The synthesized CdS nanoparticles demonstrated efficient removal of both Cr(VI) and Rhodamine B, achieving degradation efficiencies of 92 % and 95 %, respectively, within 120 min under optimized conditions. Mechanistic insights suggest the generation of reactive oxygen species (ROS) and electron-hole pairs (e-/h+) contributing to pollutant degradation. This study underscores the potential of plant-mediated CdS nanoparticles as effective photocatalysts for environmental remediation applications.

Biochar Meets Single-Atom: A Catalyst for Efficient Utilization in Environmental Protection Applications and Energy Conversion.

Single-atom catalysts (SACs), combining the advantages of multiphase and homogeneous catalysis, have been increasingly investigated in various catalytic applications. Carbon-based SACs have attracted much attention due to their large specific surface area, high porosity, particular electronic structure, and excellent stability. As a cheap and readily available carbon material, biochar has begun to be used as an alternative to carbon nanotubes, graphene, and other such expensive carbon matrices to prepare SACs. However, a review of biochar-based SACs for environmental pollutant removal and energy conversion and storage is lacking. This review focuses on strategies for synthesizing biochar-based SACs, such as pre-treatment of organisms with metal salts, insertion of metal elements into biochar, or pyrolysis of metal-rich biomass, which are more simplistic ways of synthesizing SACs. Meanwhile, this paper attempts to 1) demonstrate their applications in environmental remediation based on advanced oxidation technology and energy conversion and storage based on electrocatalysis; 2) reveal the catalytic oxidation mechanism in different catalytic systems; 3) discuss the stability of biochar-based SACs; and 4) present the future developments and challenges regarding biochar-based SACs.