Search Results (70)

Narcotics trafficking is a fundamental part of organized crime, posing significant and evolving challenges for forensic investigations. Addressing these challenges requires rapid, precise, and scientifically validated analytical methods for reliable identification of illicit substances. Over the past five years, forensic drug testing has advanced considerably, improving detection of traditional drugs—such as tetrahydrocannabinol, cocaine, heroin, amphetamine-type stimulants, and lysergic acid diethylamide—as well as emerging new psychoactive substances (NPS), including synthetic cannabinoids (e.g., 5F-MDMB-PICA), cathinones (e.g., α-PVP), potent opioids (e.g., carfentanil), designer psychedelics (e.g., 25I-NBOMe), benzodiazepines (e.g., flualprazolam), and dissociatives (e.g., 3-HO-PCP). Current technologies include colorimetric assays, ambient ionization mass spectrometry, and chromatographic methods coupled with various detectors, all enhancing accuracy and precision. Vibrational spectroscopy techniques, like Raman and Fourier transform infrared spectroscopy, have become essential for non-destructive identification. Additionally, new sensors with disposable electrodes and miniaturized transducers allow ultrasensitive on-site detection of drugs and metabolites. Advanced chemometric algorithms extract maximum information from complex data, enabling faster and more reliable identifications. An important emerging trend is the adoption of green analytical methods—including direct analysis, solvent-free extraction, miniaturized instruments, and eco-friendly chromatographic processes—that reduce environmental impact without sacrificing performance. This review provides a comprehensive overview of innovations over the last five years in forensic drug analysis based on the ScienceDirect database and highlights technological trends shaping the future of forensic toxicology. Full article

The rising demand for sustainable energy storage has fueled the development of green batteries as alternatives to conventional systems. However, a major research gap lies in the unified integration of environmentally friendly materials and processes across all battery components—electrodes, electrolytes, and separators—without compromising performance or scalability. This review addresses this gap by highlighting recent advances in eco-conscious battery technologies, focusing on green electrode fabrication using water-based methods, electrophoretic deposition, solvent-free dry-press coating, 3D printing, and biomass-derived materials. It also examines the shift toward safer electrolytes, including ionic liquids, deep eutectic solvents, water-based systems, and solid biopolymer matrices, which improve both environmental compatibility and safety. Additionally, biodegradable separators made from natural polymers such as cellulose and chitosan offer enhanced thermal stability and ecological benefits. The review emphasizes the importance of lifecycle considerations like recyclability and biodegradability, aligning battery design with circular economy principles. While significant progress has been made, challenges such as standardization, long-term stability, and industrial scalability remain. By identifying key strategies and future directions, this article contributes to the foundation for next-generation green batteries, promoting their adoption in environmentally sensitive applications ranging from wearable electronics to grid storage. Full article

Slurry-cast (SLC) electrode manufacturing faces problems such as thickness limitation and material stratification, which are caused by applying toxic organic solvents. Solvent-free electrode technology, as a sustainable alternative, could get rid of issues generated by solvents. In this study, dual-layer NCM811 solvent-free electrodes (DLEs) are fabricated via an electrostatic powder deposition method with an active material-rich upper layer to provide high energy output, while the more binder–conductor content base layer improves conductivity and contact with current collectors. The dual-layered structure overwhelms the single-layer electrode (SE) with stable cycling performance caused by more regulated pore structures. DLE maintains 74% capacity retention after 100 cycles at 0.3 C, while the SLC shows only 60% capacity retention. Additionally, DLE shows excellent rate performance at various rates, with 207.3 mAh g⁻¹, 193.9 mAh g⁻¹, 173.9 mAh g⁻¹, 157.3 mAh g⁻¹, and 120.4 mAh g⁻¹ at 0.1 C, 0.2 C, 0.5 C, 1.0 C, and 2.0 C, respectively. The well-designed DLE cathodes exhibit superior discharge-specific capacities, rate performance, and improved cycling stability than traditional SLC cathodes. It enlightens the path toward new structure innovations of solvent-free electrodes. Full article

Previous studies have demonstrated that underwater low-temperature plasma is effective for synthesizing nanomaterials by generating plasma discharges between metal electrodes submerged in water. This study extends this approach to the one-step synthesis of MXenes containing titanium, molybdenum, and titanium–molybdenum composites through pulsed discharges in carbon tetrachloride, an oxygen-free, non-flammable solvent characterized by a high boiling point and low permittivity. By employing titanium and molybdenum electrodes in various configurations, three MXene samples were synthesized: Ti₂CT_X, Mo₂CT_X, and Mo₂TiC₂T_X. Characterization techniques, including UV-Vis spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, confirmed the successful synthesis of high-purity MXenes with distinct structural and optical properties. Notably, the bandgap values of the synthesized MXenes were determined as 1.71 eV for Ti₂CT_X, 1.42 eV for Mo₂TiC₂T_X, and 1.07 eV for Mo₂CT_X. The photocatalytic performance of the synthesized MXenes was evaluated, showing a removal efficiency of 65% to 98% for dye mixtures, with methylene blue showing the highest degradation rate. This plasma-assisted method offers a scalable, precursor-free route for the synthesis of MXenes with potential applications in energy storage, environmental remediation, and optoelectronics due to their tunable bandgaps and high catalytic activity. Full article

Triboelectric separation, a solvent-free method, was investigated as a tool for protein enrichment in wheat flour. Gluten–starch model mixtures, flour, and reground flour fractions were evaluated for their separation characteristics (selectivity and efficiency). Mass yield, protein content, particle size distribution, and SEM analysis were used to assess performance. Selectivity and efficiency increased with gluten concentration, peaking at 63% for the 50% gluten mixture, but declined at higher concentrations. The 15% gluten benchmark demonstrated effective protein separation, with protein enrichment occurring in the ground electrode fraction and a corresponding depletion in the positive electrode fraction. In contrast, flour and reground flour fractions exhibited reduced separation efficiency, showing protein depletion in both electrode fractions due to agglomeration. The benchmark achieved the highest separation efficiency (47%), followed by reground flour (41%) and flour (7%). Finer particles in reground flour enhanced chargeability and GE deposition, while larger agglomerates in flour reduced efficiency, leading to material accumulation in the cups. Pre-milling helped detach protein and starch to some extent but also triggered re-agglomeration. Larger particles were influenced more by gravitational forces. These findings highlight the complexity of wheat flour fractionation and the need to optimize particle size and charge distribution to improve protein enrichment through triboelectric separation. Full article

The cathode affects the capacity, working voltage, and cost of lithium-ion batteries. Although the binder is a small part of the cathode material, it is particularly important to the performance of the batteries. Therefore, the design and development of polymer binders with different structures and characteristics is an important topic. In this paper, an NCM811 cathode (PPC-NCM) was prepared by a solvent-free method using poly (propylene carbonate) (PPC) as the binder, with an active substance loading of 10 mg/cm². To explore the effect of the PPC binder on the electrochemical performance of the NCM811 cathode, the discharge capacity was 112.2 mAh/g with a 76.1% capacity retention after cycling more than 200 cycles at 1 C, which has a significantly better cycling performance than that of a PVDF-NCM/Li battery. The PPC/NCM/graphite full cells were also assembled to demonstrate the practical application potential of this work. It was shown that PPC as a binder can improve the cycling stability of NCM811/Li and NCM811/graphite full cells. The PPC binder used in the NCM811 cathode not only makes it extremely easy to prepare dry electrodes, but also makes it very simple to recover the electrode material by heating in the case of battery failure. This paper provides a new idea for the industrialization and development of a novel binder. Full article

The extensive use of the alkaloid quinine (QN) in the cosmetic and food industries has induced major concerns relating to its impact on human health, considering its potential toxicity. Therefore, developing sensitive and selective electrochemical sensors is crucial for monitoring QN in environmental, food, and pharmaceutical samples. To respond to this need, a surfactant-supported green synthesis approach, based on a straightforward, organic solvent-free hydrothermal method was employed to synthesize highly crystalline pseudospherical bismuth oxychloride (BiOCl) nanoparticles. This material was used for the enrichment of carbon paste electrodes and its further utilization for the detection and quantification of quinine. They have superior electrocatalytic performance, due to their size and morphology, and facilitate the interactions of the target with the electrode surface. Under optimal operating conditions, differential pulse voltammetry demonstrated a remarkable feature: a broad linear working range of 10 to 140 μM, a detection limit of 0.14 μM, and a high sensitivity of 1.995 μA μM⁻¹ cm⁻². The suggested method’s satisfactory sensitivity, along with its good stability, repeatability, and reproducibility, strongly point to a possible use for identifying quinine in real samples. Full article

Cobaltocenium-containing (co)polysiloxanes (Cc-PDMSs) with terminal and side groups were synthesized by the reaction of catalyst-free hydroamination between ethynylcobaltocenium hexafluorophosphate and polysiloxanes comprising amino moieties as terminal and side groups. The conversion of NH₂ groups in the polymers reaches 85%. The obtained (co)polysiloxanes “gelate” due to an increase in their molecular weight by approx. 30 times, when stored at room temperature over one week. “Gelated” Cc-PDMSs remain soluble in most polar solvents. The structure of Cc-PDMSs and the mechanism of “gelation” were established by ¹H, ¹³C{¹H}, ²⁹Si{¹H}, ¹⁹F{¹H}, ³¹P{¹H} nuclear magnetic resonance, infrared, ultraviolet–visible, and X-ray photoelectron spectroscopies. As determined by cyclic voltammetry, Cc-PDMSs possess redox properties (Co^II/Co^III transitions at E_1/2 = −1.8 and −1.3 V before and after “gelation”, respectively). This synthetic approach allows to increase the molecular weights of the synthesized polysiloxanes functionalized with cobaltocenium groups easily, leading to their higher film-forming ability, which is desirable for some electronic applications. Cc-PDMSs can be utilized as redox-active polymer films in modified electrodes, electrochromic devices, redox-active coatings, and components for batteries. Full article

The safety concerns associated with current lithium-ion batteries are a significant drawback. A short-circuit within the battery’s internal components, such as those caused by a car accident, can lead to ignition or even explosion. To address this issue, a polymer shear thickening electrolyte, free from flammable solvents, has been developed. It comprises a star-shaped oligomer derived from a trimethylolpropane (TMP) core and polyether chains, along with the inclusion of 20 wt.% nanosilica. Notably, the star-shaped oligomer serves a dual function as both the solvent for the lithium salt and the continuous phase of the shear thickening fluid. The obtained electrolytes exhibit an ionic conductivity of the order of 10⁻⁶ S cm⁻¹ at 20 °C and 10⁻⁴ S cm⁻¹ at 80 °C, with a high Li⁺ transference number (t₊ = 0.79). A nearly thirtyfold increase in viscosity to a value of 1187 Pa s at 25 °C and a critical shear rate of 2 s⁻¹ were achieved. During impact, this electrolyte could enhance cell safety by preventing electrode short-circuiting. Full article

Supercapacitors hold promise for energy storage due to their exceptional power density and fast charge/discharge cycles. However, their performance hinges on the electrode material. Zeolitic imidazolate frameworks (ZIFs) are attractive options due to their tailorable structure and high surface area. But traditional ZIF synthesis relies on toxic solvents derived from fossil fuels, hindering their envisioned environmental benefit. This study explores using bio-derived solvents for a greener and potentially superior approach. The researchers employed anodic electrodeposition to synthesise cobalt-based ZIFs (Co-ZIFs) as supercapacitor electrode materials. Two linkers (2-methylimidazole and benzimidazole) and two bio-derived solvents (Cyrene^TM and γ-valerolactone (GVL)) were investigated. X-ray diffraction analysis revealed that bio-derived solvents enhanced the crystallinity of Co-ZIFs compared to traditional solvents. Notably, Cyrene^TM promoted better crystallinity for Co-bIM/Co-mIM structures. The Full Width at Half Maximum (FWHM) analysis suggests Cyrene^TM promotes Co-bIM/Co-mIM crystallinity (lower FWHM). Co-mIM in Cyrene^TM exhibits the best crystallinity (FWHM = 0.233) compared to other ZIF samples. Scanning electron microscopy confirmed these findings, showing larger and well-defined crystals for bio-derived solvent-synthesised ZIFs. The choice of solvent significantly impacted the final ZIF structure. While 2-methylimidazole consistently formed ZIF-67 regardless of the solvent, benzimidazole exhibited solvent-dependent behaviour. GVL yielded the highly porous Co-ZIF-12 structure, whereas DMF (N,N-dimethylformamide) and Cyrene^TM produced the less porous ZIF-9. This work reports the first-ever instance of ZIF-12 synthesis via an electrochemical method, highlighting the crucial interplay between solvent and precursor molecule in determining the final ZIF product. The synthesised binder-free Co-ZIF electrodes were evaluated for supercapacitor performance. The capacitance data revealed GVL as the most effective solvent, followed by DMF and then Cyrene^TM. This suggests GVL is the preferred choice for this reaction due to its superior performance. The ZIF-12-based electrode exhibits an impressive specific capacitance (C_sp) of 44 F g⁻¹, significantly higher than those achieved by ZIF-9-Cyrene (1.2 F g⁻¹), ZIF-9-DMF (2.5 F g⁻¹), ZIF-67-GVL (35 F g⁻¹), ZIF-67-Cyrene (6 F g⁻¹), and ZIF-67-DMF (16 F g⁻¹) at 1 A g⁻¹. This surpasses the C_sp of all other ZIFs studied, including high-performing ZIF-67(GVL). ZIF-12(GVL) maintained superior C_sp even at higher current densities, demonstrating exceptional rate capability. Among the bio-derived solvents, GVL outperformed Cyrene^TM. Notably, the Co-bIM in the GVL sample exhibited a ZIF-12-like structure, offering potential advantages due to its larger pores and potentially higher surface area compared to traditional ZIF-67 and ZIF-9 structures. This work presents a significant advancement in Co-ZIF synthesis. By utilising bio-derived solvents, it offers a more sustainable and potentially superior alternative. This paves the way for the eco-friendly production of Co-ZIFs with improved properties for supercapacitors, gas separation, catalysis, and other applications. Full article

With the increasing demand for Li resources worldwide, the easy recycling of Li-ion batteries materials becomes essential. We report a binder-free cathode consisting of carbon nanotubes (CNTs) and LiFePO₄ (LFP) nanoparticles embedded in a 3D Al network. The electrode stability depends on the CNT ratio, where 3% CNT-wrapping LFPs provide a stable structure free of detachment from Al foam, as observed on Al foil. The binder-free cathode sheet exhibited excellent performance for high-rate discharge and long-term cycle life. Materials on the cathode can be easily detached with ultrasonic treatment when immersed in organic solvent, which is advantageous for a green and high-efficiency strategy of recycling all valuable materials compared to the binder-used electrode. Full article

The binder ratio in a commercial lithium-ion battery is very low, but it is one of the key materials affecting the battery’s performance. In this paper, polycarbonate-based polymers with liner or chain extension structures are proposed as binders. Then, dry LiFePO₄ (LFP) electrodes with these binders are prepared using the solvent-free method. Polycarbonate-based polymers have a high tensile strength and a satisfactory bonding strength, and the rich polar carbonate groups provide highly ionic conductivity as binders. The batteries with poly (propylene carbonate)-plus (PPC-P) as binders were shown to have a long cycle life (350 cycles under 1 C, 89% of capacity retention). The preparation of dry electrodes using polycarbonate-based polymers can avoid the use of solvents and shorten the process of preparing electrodes. It can also greatly reduce the manufacturing cost of batteries and effectively use industrial waste gas dioxide oxidation. Most importantly, a battery material with this kind of polycarbonate polymer as a binder is easily recycled by simply heating after the battery is discarded. This paper provides a new idea for the industrialization and development of a novel binder. Full article

The efficient dispersion of single-walled carbon nanotubes (SWCNTs) has been the subject of extensive research over the past decade. Despite these efforts, achieving individually dispersed SWCNTs at high concentrations remains challenging. In this study, we address the limitations associated with conventional methods, such as defect formation, excessive surfactant use, and the use of corrosive solvents. Our novel dispersion method utilizes the spontaneous charging of SWCNTs in a solvated electron system created by dissolving potassium in hexamethyl phosphoramide (HMPA). The resulting charged SWCNTs (c-SWCNTs) can be directly dispersed in the charging medium using only magnetic stirring, leading to defect-free c-SWCNT dispersions with high concentrations of up to 20 mg/mL. The successful dispersion of individual c-SWCNT strands is confirmed by their liquid-crystalline behavior. Importantly, the dispersion medium for c-SWCNTs exhibits no reactivity with metals, polymers, or other organic solvents. This versatility enables a wide range of applications, including electrically conductive free-standing films produced via conventional blade coating, wet-spun fibers, membrane electrodes, thermal composites, and core-shell hybrid microparticles. Full article

The growing interest in hybrid (aqueous–organic) electrolytes for electrochemical energy storage is due to their wide stability window, improved safety, and ease of assembly that does not require a moisture-free atmosphere. When it comes to applications in electrochemical capacitors, hybrid electrolytes are expected to fill the gap between high-voltage organic systems and their high discharge rate aqueous counterparts. This article discusses the potential applicability of aqueous–organic electrolytes utilizing water/N,N-dimethylacetamide (DMAc) solvent mixture, and sodium perchlorate as a source of charge carriers. The hydrogen bond formation between H₂O and DMAc (mole fraction x_DMAc = 0.16) is shown to regulate the original water and cation solvation structure, thus reducing the electrochemical activity of the primary aqueous solution both in the hydrogen (HER) and oxygen (OER) evolution reactions region. As a result, an electrochemical stability window of 3.0 V can be achieved on titanium electrodes while providing reasonable ionic conductivity of 39 mS cm⁻¹ along with the electrolyte’s flame retardant and anti-freezing properties. Based on the diagnostic electrochemical studies, the operation conditions for carbon/carbon capacitors have been carefully optimized to adjust the potential ranges of the individual electrodes to the electrochemical stability region. The system with the appropriate electrode mass ratio (m₊/m₋ = 1.51) was characterized by a wide operating voltage of 2.0 V, gravimetric energy of 13.2 Wh kg⁻¹, and practically a 100% capacitance retention after 10,000 charge–discharge cycles. This translates to a significant rise in the maximum energy of 76% when compared to the aqueous counterpart. Additionally, reasonable charge–discharge rates and anti-freeze properties of the developed electrolyte enable application in a broad temperature range down to −20 °C, which is demonstrated as well. Full article

Among the conventional inks used for inkjet printing, metals, oxides, or polymers have been deposited in order to form functional coatings. Gold is one of the most used metals for electrode fabrication in the gas sensor field due to its inert behavior when exposed to reactive gases and conductive properties. However, only a few commercial gold inks are commercially available, and the combination of excessive price, a high minimum purchase quantity, and an unknown composition renders the actual products unappealing. To meet these shortcomings, gold inks were formulated with different solvents in order to reach sufficient properties for the inkjet printing process, such as surface tension and viscosity. On the one hand, gold ink was developed using a gold nanoparticle (AuNP) solution as the metal. This ink was optimized from nanoparticle synthesis, with the ink formulation obtaining a 32 mN·m⁻¹ surface tension and 11.2 mPa·s viscosity in order to be inkjet-printed onto polyimide foil. On the other hand, a particle-free ink, called a precursor based of ink, was also developed. In this case, ink was made by solubilizing gold salt in aqueous medium in order to reach jettable properties. Surface tension was measured at 32 mN·m⁻¹ while viscosity was 14.0 mPa·s. Then, printing and deposition parameters were optimized in order to obtain a highly conductive gold coating. The measured resistivity was 2 × 10⁻⁷ Ω·m which is close to the bulk gold conductive value. These coatings could be used for the fabrication of various devices in different working fields. Full article