Thomas Alva Edison was an American inventor famous for his breakthroughs in stable electric lighting. He founded one of the first modern research laboratories in Menlo Park, New Jersey, United States and invented the first commercially viable electric lightbulb in 1879. Here, we recreated conditions similar to those used by Edison to produce his original carbon filament light bulb and show that the carbon filament was converted into graphene. This suggests that Edison might have indeed formed the same in his experiments 145 years ago.

Per- and polyfluoroalkyl substances (PFAS) are recalcitrant and bioaccumulative environmental pollutants. Whereas substantial efforts have been made to degrade PFAS, the potential for effectively using these fluoride resources has been overlooked. Here we develop an electrothermal fluorination method to selectively fluorinate brine salts using granular activated carbon (GAC)-sorbed aqueous film-forming foam (AFFF) as a fluorination agent. During this process, GAC and PFAS in AFFF are converted to graphene, whereas fluorine atoms are effectively mineralized into metal fluorides. Followed by washing and flash distillation, lithium can be recovered from other alkali and alkaline-earth metal cations in brine (Na+, Mg2+, K+, Ca2+) in the form of lithium fluoride, with an similar to 99% lithium purity and similar to 82% yield. The recovered lithium fluoride is demonstrated as an additive to stabilize electrolytes and improve the performance of lithium-ion batteries. Life-cycle assessment and techno-economic analysis indicate that this process greatly reduces greenhouse gas emissions and costs compared to the industrial lithium extraction method. This highlights the potential of the process to manage pollutants while providing a sustainable lithium supply, and this fluorination strategy shows promise to be extended to other metal extraction processes.

Thomas Alva Edison was an American inventor famous for his breakthroughs in stable electric lighting. He founded one of the first modern research laboratories in Menlo Park, New Jersey, United States, and invented the first commercially viable electric lightbulb in 1879. Here, we recreated conditions like those used by Edison to produce his original carbon filament light bulb and show that the carbon filament was converted into graphene. This suggests that Edison might have indeed formed the same in his experiments 145 years ago.

The rising demand for lithium-ion batteries (LIBs) highlights the urgent need for sustainable recycling technologies. Existing pyrometallurgy and hydrometallurgy methods can recover valuable metals but suffer from high energy costs and wastewater generation. Here, a selective flash Joule heating chlorination and oxidation (FJH-ClO) strategy is presented for the efficient separation of metals from spent batteries. In this process, cathode metals are first chlorinated for 60 s, after which the transition metal chlorides are oxidized to oxides, enabling lithium to be separated from transition metals due to their different aqueous solubility. This approach applies not only to the recovery of metals from lithium cobalt oxide (LCO), lithium iron phosphate (LFP), and lithium manganese iron phosphate (LMFP) cathode materials, but also to the anodic graphite, all from the black mass. The recovered graphite exhibits purity of ≈100% with a yield of 85%, Co at 99% purity and 97% yield, and Li at 99% purity with a 92% yield. Gram-scale experiments confirm the scalability of the method, maintaining high efficiency and selectivity. Life-cycle assessment and technoeconomic analysis reveal that the FJH-ClO process substantially reduces energy consumption, operation time, and reagent consumption, while lowering operating costs by up to 92%, compared to conventional approaches.

Aluminum is one of the most produced metals worldwide. The Bayer process extracts aluminum from bauxite ores and generates bauxite residue as an environmentally hazardous waste with a low recycling rate and increasing accumulation. The high Fe content in the residue makes it cost prohibitive to extract the remaining aluminum. We present here a process using flash Joule heating combined with chlorination (FJH-Cl2) to remove iron and heavy metals from bauxite residues. With one-step FJH-Cl2 treatment in 1 min, >96% of the Fe can be removed as volatile FeCl3 from bauxite residues while retaining ∼ 99% of the Al in the residue. The corundum-rich residue can be sintered into high-performing ceramics, underscoring the valorization of the bauxite residue. Life-cycle assessment and techno-economic analysis show that the FJH-Cl2 process has far lower global warming emissions, energy consumption, and costs when compared to alternative processes. This highlights the potential of FJH-Cl2 as an efficient method for upcycling bauxite residues into valuable Al resources and high-performance materials.

Metal recycling plays a crucial role in mitigating the critical metals shortage and reducing reliance on primary mining. Current liquid hydrometallurgy involves significant water and chemical consumption with troublesome secondary waste streams, while pyrometallurgy lacks selectivity and requires substantial energy input. Here we develop an electrothermal chlorination and carbochlorination process, and a specialized compact reactor, for the selective separation of individual critical metals from electronic waste. Our approach uses programmable, pulsed current input to achieve precise control over a wide temperature range (from room temperature to 2400 °C), short reaction duration of seconds, and rapid heating/cooling rates (103 °C s-1) during the process. The method capitalizes on the differences in the free energy formation of the metal chlorides. Once conversion to a specific metal chloride is achieved, that compound distills from the mixture in seconds. This allows for both thermodynamic and kinetic selectivity for desired metals with minimization of impurities.

The increasing use of fibre-reinforced plastics (FRPs) has triggered an urgent need for proper end-of-life management strategies. Currently, most adopted methods are landfilling, incineration and solvolysis, which lead to undesirable environmental contamination and waste of resources. To address this issue, we develop a solvent-free and energy-efficient flash upcycling method enabling ultrafast conversion of the mixture of different FRPs to SiC, a widely used reinforcement and semiconducting material, with high yields (>90%). By tuning operation conditions, SiC with two different phases, 3C-SiC and 6H-SiC, can be selectively synthesized with high phase purity (90–99%). The obtained SiC powders can be used as the anode material for lithium-ion batteries. The 3C-SiC anode exhibits superior reversible capacity and rate performance at 0.2 C over the 6H-SiC anode (741 mAh g−1 vs 626 mAh g−1), while both show good cycling stability. Life cycle assessment reveals that the flash upcycling method developed here greatly reduces the energy demand, greenhouse gas emissions and water consumption over other available FRP disposal methods. Overall, this work provides a viable method for sustainable management of end-of-life FRPs, contributing to clean production and circular economy. Sustainable end-of-life management strategies for fibre-reinforced plastics are urgently needed from a sustainability perspective. Here the authors develop a solvent-free flash upcycling method, enabling ultrafast and efficient upcycling of fibre-reinforced plastics to fulfil such a need.

Effective recycling of end-of-life Li-ion batteries (LIBs) is essential due to continuous accumulation of battery waste and gradual depletion of battery metal resources. The present closed-loop solutions include destructive conversion to metal compounds, by destroying the entire three-dimensional morphology of the cathode through continuous thermal treatment or harsh wet extraction methods, and direct regeneration by lithium replenishment. Here, we report a solvent- and water-free flash Joule heating (FJH) method combined with magnetic separation to restore fresh cathodes from waste cathodes, followed by solid-state relithiation. The entire process is called flash recycling. This FJH method exhibits the merits of milliseconds of duration and high battery metal recovery yields of ~98%. After FJH, the cathodes reveal intact core structures with hierarchical features, implying the feasibility of their reconstituting into new cathodes. Relithiated cathodes are further used in LIBs, and show good electrochemical performance, comparable to new commercial counterparts. Life-cycle-analysis highlights that flash recycling has higher environmental and economic benefits over traditional cathode recycling processes.

The flash Joule heating (FJH) method converts many carbon feedstocks into graphene in milliseconds to seconds using an electrical pulse. This opens an opportunity for processing low or negative value resources, such as coal and plastic waste, into high value graphene. Here, we demonstrate a lab-scale automation FJH system that allows the synthesis of 1.1 kg of turbostratic flash graphene from coal-based metallurgical coke (MC) in 1.5 h. The process is based on the automated conversion of 5.7 g of MC per batch using an electrical pulse width modulation system to conduct the bottom-up upcycle of MC into flash graphene. We then compare this method to two other scalable graphene synthesis techniques by both a life cycle assessment and a technoeconomic assessment.

Flash Joule heating has been used as a versatile solid-state synthesis method in the production of a wide range of products, including organic, inorganic, and ceramic products. Conventional flash Joule heating systems are large and customized, presenting significant barriers in the cost of assembly, the expertise needed to operate, and uniformity of results between different systems. Even laboratory-scale flash Joule heating systems struggle to operate above 10 g capacity, and they suffer from poor temperature controllability. We present here the use of commercial off-the-shelf arc welders as a superior alternative to standard flash Joule heating systems due to their low cost ($120), ease of use, compact size, high temperature controllability, and tunability. We demonstrate the gram-scale synthesis of a variety of organic and ceramic species using these systems. With the addition of another reactor configuration for only $260, we scale up the synthesis of these products to record rates for the laboratory scale, achieving a production rate of 3 kg/h for graphene and kilogram-per-day production rates for SiC, carbon nanotubes, SnSe2, and SnS2.

Solid-state batteries (SSBs) are poised to replace traditional organic liquid-electrolyte lithium-ion batteries due to their higher safety and energy density. Oxide-based solid electrolytes (SEs) are particularly attractive for their stability in air and inability to ignite during thermal runaway. However, achieving high-performance in oxide-based SSBs requires the development of an intimate and robust SE-cathode interface to overcome typically large interfacial resistances. The transition interphase should be both physically and chemically active. This study presents a thin, conductive interphase constructed between lithium aluminum titanium phosphate and lithium cobalt oxide using a rapid sintering method that modifies the interphase within 10 s. The rapid heating and cooling rates restrict side reactions and interdiffusion on the interface. SSBs with thick composite cathodes demonstrate a high initial capacity of ≈120 mAh g-1 over 200 cycles at room temperature. Furthermore, the rapid sintering method can be extended to other cathode systems under similar conditions. These findings highlight the importance of constructing an appropriate SE-cathode interface and provide insight into designing practical SSBs.

The increasing use of fiber-reinforced plastic has triggered an urgent demand for its recycling once it reaches its end-of-life. Currently, landfilling and incineration are major disposal methods of fiber-reinforced plastic, which lead to undesirable waste of resources and environmental contamination. To address this issue, we disclose a solvent-free and energy-efficient flash upcycling method to convert the mixture of glass fiber-reinforced plastic and carbon fiber-reinforced plastic into SiC powders within seconds and in yields of >90%. By modulating input pulse voltages and flash times, SiC with two different phases, 3C-SiC and 6H-SiC, can be selectively synthesized, each with phase purity of 90-99%. Theoretical simulations reveal that the increasing content of Si vacancy during flash process dominates the phase transformation from 3C-SiC to 6H-SiC. The SiC powders are further used as the anode material for lithium-ion batteries, which yields a phase-dependent performance. The 3C-SiC anode exhibits superior reversible capacity (741 mAh·g-1 at 0.2 C) and rate performance over the 6H-SiC anode (626 mAh·g-1 at 0.2 C), while both show excellent cycling stability (~95% capacity retention after 200 cycles). Life cycle assessment reveals the flash upcycling process greatly reduces the energy demand, greenhouse gas emission and water consumption over other recycling processes.

Soil contamination is an environmental issue due to increasing anthropogenic activities. Existing processes for soil remediation suffer from long treatment time and lack generality because of different sources, occurrences, and properties of pollutants. Here, we report a high-temperature electrothermal process for rapid, water-free remediation of multiple pollutants in soil. The temperature of contaminated soil with carbon additives ramps up to 1000 to 3000 °C as needed within seconds via pulsed direct current input, enabling the vaporization of heavy metals like Cd, Hg, Pb, Co, Ni, and Cu, and graphitization of persistent organic pollutants like polycyclic aromatic hydrocarbons. The rapid treatment retains soil mineral constituents while increases infiltration rate and exchangeable nutrient supply, leading to soil fertilization and improved germination rates. We propose strategies for upscaling and field applications. Techno-economic analysis indicates the process holds the potential for being more energy-efficient and cost-effective compared to soil washing or thermal desorption.

Plastic waste (PW) from textile and construction industries is rarely recycled due to the lack of economical and effective commercial recycling technologies. In this work, PW from these two sources is successfully converted into a microporous sorbent that is highly selective to carbon dioxide (CO 2 ) adsorption. The synthesis of the sorbent is achieved by the pyrolysis of PW in the presence of a potassium salt activator. The properties of the sorbent can be tuned by changing the parent plastic type to get varying degrees of microporosity, surface area, and nitrogen content. The best performer, a sorbent derived from nylon 6,12, had a CO 2 uptake of 19 wt% (4.32 mmol g −1 ) and 5 wt% (1.1 mmol g −1 ) at 1 and 0.1 bar, respectively. The initial estimated cost of synthesizing the sorbent is ≈$531 tonne −1 of PW making this process economically attractive compared to competitive technologies. The sorbent effectiveness in CO 2 separation is demonstrated from various feeds including simulated flue gas and direct air capture. Thus, this upcycling approach can help to address two environmental challenges: PW pollution and increased atmospheric CO 2 levels.

Hydrogen gas (H2) is the primary storable fuel for pollution-free energy production, with over 90 million tonnes used globally per year. More than 95% of H2 is synthesized through metal-catalyzed steam methane reforming that produces 11 tonnes of CO2 per tonne H2. “Green H2” from water electrolysis using renewable energy produces sub-stoichiometric CO2, but costs 2-3x more, making it presently economically unviable. Here we report catalyst-free conversion of waste plastic into clean “flash H2” along with high purity graphene. The scalable procedure evolves no CO2 when deconstructing polyolefins and produces H2 in purities up to 94% at high mass yields. Sale of the graphene byproduct at just 5% of its current value yields H2 production at negative cost. Life-cycle assessment demonstrates a 39-84% reduction in emissions compared to other H2 production methods, suggesting the flash H2 process to be an economically viable, clean H2 production route.

The staggering accumulation of end-of-life lithium-ion batteries (LIBs) and the growing scarcity of battery metal sources have triggered an urgent call for an effective recycling strategy. However, it is challenging to reclaim these metals with both high efficiency and low environmental footprint. We use here a pulsed dc flash Joule heating (FJH) strategy that heats the black mass, the combined anode and cathode, to >2100 kelvin within seconds, leading to ~1000-fold increase in subsequent leaching kinetics. There are high recovery yields of all the battery metals, regardless of their chemistries, using even diluted acids like 0.01 M HCl, thereby lessening the secondary waste stream. The ultrafast high temperature achieves thermal decomposition of the passivated solid electrolyte interphase and valence state reduction of the hard-to-dissolve metal compounds while mitigating diffusional loss of volatile metals. Life cycle analysis versus present recycling methods shows that FJH significantly reduces the environmental footprint of spent LIB processing while turning it into an economically attractive process.

Heteroatom doping can effectively tailor the local structures and electronic states of intrinsic two-dimensional materials, and endow them with modified optical, electrical, and mechanical properties. Recent studies have shown the feasibility of preparing doped graphene from graphene oxide and its derivatives via some post-treatments, including solid-state and solvothermal methods, but they require reactive and harsh reagents. However, direct synthesis of various heteroatom-doped graphene in larger quantities and high purity through bottom-up methods remains challenging. Here, we report catalyst-free and solvent-free direct synthesis of graphene doped with various heteroatoms in bulk via flash Joule heating (FJH). Seven types of heteroatom-doped flash graphene (FG) are synthesized through millisecond flashing, including single-element-doped FG (boron, nitrogen, oxygen, phosphorus, sulfur), two-element-co-doped FG (boron and nitrogen), as well as three-element-co-doped FG (boron, nitrogen, and sulfur). A variety of low-cost dopants, such as elements, oxides, and organic compounds are used. The graphene quality of heteroatom-doped FG is high, and similar to intrinsic FG, the material exhibits turbostraticity, increased interlayer spacing, and superior dispersibility. Electrochemical oxygen reduction reaction of different heteroatom-doped FG is tested, and sulfur-doped FG shows the best performance. Lithium metal battery tests demonstrate that nitrogen-doped FG exhibits a smaller nucleation overpotential compared to Cu or undoped FG. The electrical energy cost for the synthesis of heteroatom-doped FG synthesis is only 1.2 to 10.7 kJ g-1, which could render the FJH method suitable for low-cost mass production of heteroatom-doped graphene.

The ever-increasing production of commercial lithium-ion batteries (LIBs) will result in a staggering accumulation of waste when they reach their end of life. A closed-loop solution, with effective recycling of spent LIBs, will lessen both the environmental impacts and economic cost of their use. Presently, <5% of spent LIBs are recycled and the regeneration of graphite anodes has, unfortunately, been mostly overlooked despite the considerable cost of battery-grade graphite. Here, an ultrafast flash recycling method to regenerate the graphite anode is developed and valuable battery metal resources are recovered. Selective Joule heating is applied for only seconds to efficiently decompose the resistive impurities. The generated inorganic salts, including lithium, cobalt, nickel, and manganese, can be easily recollected from the flashed anode waste using diluted acid, specifically 0.1 m HCl. The flash-recycled anode preserves the graphite structure and is coated with a solid-electrolyte-interphase-derived carbon shell, contributing to high initial specific capacity, superior rate performance, and cycling stability, when compared to anode materials recycled using a high-temperature-calcination method. Life-cycle-analysis relative to current graphite production and recycling methods indicate that flash recycling can significantly reduce the total energy consumption and greenhouse gas emission while turning anode recycling into an economically advantageous process.

Plastic waste (PW) and increasing atmospheric carbon dioxide (CO2) levels are among the top environmental concerns presently facing humankind. With an ambitious 2050 zero-CO2 emissions goal, there is a demand for economical CO2 capture routes. Here we show that the thermal treatment of PW in the presence of potassium acetate yields an effective carbon sorbent with pores width of 0.7-1.4 nm for CO2 capture. The PW to carbon sorbent process works with single or mixed streams of polyolefin plastics. The CO2 capacity of the sorbent at 25 °C is 17.0 ± 1.1 wt % (3.80 ± 0.25 mmol g-1) at 1 bar and 5.0 ± 0.6 wt % (1.13 ± 0.13 mmol g-1) at 0.15 bar, and it regenerates upon reaching 75 ± 5 °C. The CO2 capture cost from flue gas via this technology is estimated to be <$21 ton-1 CO2, much lower than competing CO2 capture technologies. Hence, this PW-derived carbon material should find utility in the capture of CO2 from point sources of high CO2 emissions while providing a use for otherwise deleterious PW.

Laser‐induced graphene (LIG) can be patterned on a variety of substrates using a laser scriber/cutter. The quality and morphology of LIG is currently analyzed using Raman spectroscopy and electron microscopy. Here a method is presented to enable analysis of LIG in real‐time during the synthesis using a microphone attached to the laser writing head, followed by a simple acoustic signal processing scheme. It is demonstrated that it is possible to use the same energy input to simultaneously drive the conversion process and probe the formation of LIG in situ by applying Fourier and integral analyses, thus allowing rapid, high‐throughput determination of the local quality and morphology of the produced LIG.