It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Tuesday, June 16, 2026
Biochar helps redesign catalyst chemistry for faster pesticide removal from water
Biochar Editorial Office, Shenyang Agricultural University
Biochar-regulated LDH-derived Co–Mn spinel for non-radical peroxymonosulfate activation: high-efficiency imidacloprid degradation dominated by high-valent metal–oxo species and singlet oxygen
Credit: Xiaolong Dong, Yongzhen Ding, Xiaohu Fan, Fuxiang Zhang, Fengyang Pan, Zulin Zhang, Qiang Fu & Song Cui
A new biochar-regulated catalyst can remove 96.9% of the widely used insecticide imidacloprid from water within 40 minutes, offering a promising route for treating pesticide-contaminated wastewater.
Neonicotinoid insecticides have become an important part of modern agriculture, but their persistence in water has raised growing ecological concerns. Among them, imidacloprid is one of the most widely used and frequently detected compounds. Because it can threaten aquatic invertebrates even at very low concentrations, researchers are looking for faster, more stable, and more selective ways to break it down before it reaches sensitive ecosystems.
In a new study published in Biochar, researchers developed a cobalt manganese spinel catalyst regulated by biochar and derived from layered double hydroxides. The optimized material, named CoMn0.75/BC, activated peroxymonosulfate, a common oxidant used in advanced water treatment, and achieved 96.9% removal of 5 mg L−1 imidacloprid within 40 minutes. Its degradation rate was substantially higher than systems using biochar or cobalt manganese oxide alone.
“Biochar is not only a support material in this system. It actively changes how the catalyst works, steering the reaction toward more selective non-radical oxidation pathways,” said the study’s corresponding authors. “This provides a useful design strategy for next-generation catalysts used in pesticide wastewater treatment.”
Many advanced oxidation processes rely heavily on radical species, which can be powerful but are often sensitive to pH, background ions, and natural organic matter in real water. In contrast, the new CoMn0.75/BC system shifted the reaction toward non-radical pathways dominated by high-valent metal oxo species and singlet oxygen. These species can offer more selective oxidation and better resistance to interference from complex water components.
The research team found that biochar played several connected roles. Its porous structure helped disperse cobalt manganese spinel nanoparticles and prevent aggregation. Its oxygen-containing functional groups, especially carbonyl groups, helped chelate cobalt and manganese ions and stabilize high-valent metal oxo species. In addition, persistent free radicals naturally bound to the biochar surface promoted singlet oxygen generation during peroxymonosulfate activation.
The catalyst also showed strong practical potential. It maintained more than 85% imidacloprid removal across a wide pH range from 3 to 11, indicating that it could operate under varied wastewater conditions. Common ions such as chloride and sulfate had little influence on performance, consistent with the system’s non-radical-dominated mechanism. The catalyst remained active in tap water and several surface water samples, with strong tolerance to realistic water matrices.
Reusability tests further supported the material’s stability. After five cycles, imidacloprid removal decreased only slightly, from 96.9% to 91.3%. The spinel crystal structure was retained after reaction, and metal leaching remained low. In a continuous-flow column experiment designed to simulate practical treatment, the catalyst-packed system maintained over 80% imidacloprid removal after 420 minutes of operation.
The system also degraded other neonicotinoid insecticides, including thiamethoxam, clothianidin, dinotefuran, and nitenpyram, suggesting broader applicability beyond imidacloprid. The authors note that while the catalyst showed promising durability, longer continuous operation tests and techno-economic analysis will be needed before full-scale application.
“By using biochar to regulate both catalyst structure and reaction pathway, we can move beyond simple pollutant adsorption and toward efficient catalytic detoxification,” the authors said. “This work highlights how biomass-derived carbon materials can be engineered to address emerging water pollution challenges.”
The findings offer a rational blueprint for designing biochar hybrid catalysts capable of treating high-strength industrial wastewater contaminated with neonicotinoid insecticides.
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Journal Reference: Dong, X., Ding, Y., Fan, X. et al. Biochar-regulated LDH-derived Co–Mn spinel for non-radical peroxymonosulfate activation: high-efficiency imidacloprid degradation dominated by high-valent metal–oxo species and singlet oxygen. Biochar8, 109 (2026).
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
Biochar-regulated LDH-derived Co–Mn spinel for non-radical peroxymonosulfate activation: high-efficiency imidacloprid degradation dominated by high-valent metal–oxo species and singlet oxygen
Article Publication Date
12-Jun-2026
Turning lavender waste into a high-performance sensor for safer ethylene glycol detection
Biochar Editorial Office, Shenyang Agricultural University
A new study has shown that agricultural waste from lavender straw can be transformed into a highly sensitive biochar-based sensor for detecting ethylene glycol, a widely used but potentially toxic chemical found in products such as antifreeze and industrial solvents.
Published in Biochar, the study reports a green and controllable strategy for engineering the tiny pores and surface defects of biochar derived from lavender straw nanocellulose. By carefully adjusting the hydrolysis time during material preparation, the research team created a sensor material that can detect ethylene glycol at room temperature with high sensitivity, a low detection limit, and long-term stability.
“Our work shows that agricultural residues can be more than waste. With precise structural design, they can become advanced functional materials for public safety and environmental monitoring,” said corresponding author Professor Zhaofeng Wu of Xinjiang University. “The key was learning how hydrolysis time controls the internal structure of the biochar.”
Ethylene glycol is commonly used in antifreeze, polyester production, and other industrial processes. However, exposure to ethylene glycol can pose health risks, including effects on the central nervous system and damage to multiple organs. Fast and reliable detection is therefore important for workplace safety, automotive maintenance, industrial inspection, and environmental monitoring.
The team selected lavender straw, an underused agricultural residue from Xinjiang, as the starting material. Lavender straw has a loose fibrous structure and naturally contains calcium, making it suitable for producing biochar with useful sensing properties. The researchers first extracted nanocellulose from the straw using an oxalic acid and acetic acid hydrolysis process, then converted it into biochar through carbonization.
The most important finding was that hydrolysis time acted as a structural “control knob.” When the treatment time was too short, the nanocellulose did not fully separate, limiting pore formation. When the treatment was too long, the structure became damaged and compacted. A moderate hydrolysis time of 3 hours produced the best material, named CLN-3.
CLN-3 formed an open mesoporous network with a specific surface area of 46.36 m² g⁻¹ and abundant oxygen-related surface sites. These features helped ethylene glycol molecules enter the material, interact with the surface, and trigger a strong electrical response.
In testing, the CLN-3 sensor showed an exceptional response of 17,576.67% toward ethylene glycol at room temperature, with a low detection limit of 0.36 ppm. It also maintained stable operation over 40 days and showed repeatable performance over multiple sensing cycles. Compared with many conventional ethylene glycol sensors that require elevated operating temperatures, this room-temperature performance could help reduce energy use and support portable or on-site detection devices.
To better understand why the material performed so well, the researchers combined experimental testing with density functional theory calculations. The calculations showed that naturally present calcium in the lavender-derived biochar enhanced the adsorption of ethylene glycol, increasing adsorption energy from −0.13674 eV to −0.39508 eV when calcium doping and pre-adsorbed oxygen worked together. This stronger interaction promoted charge transfer at the sensor surface, improving the sensing signal.
“The synergy between pores, oxygen vacancies, and natural calcium doping gives the biochar its strong sensing ability,” said corresponding author Hua Zhuo. “This provides a practical design principle for developing low-cost sensors from biomass resources.”
The researchers also demonstrated the sensor’s potential for antifreeze detection in laboratory tests. While further calibration and field validation are still needed for complex real-world environments, the study offers a promising route toward sustainable, low-cost, and sensitive detection technologies.
By converting lavender straw into a functional sensing material, the work highlights a broader opportunity: agricultural byproducts can serve as valuable building blocks for next-generation environmental and safety monitoring devices.
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Journal Reference: Gong, Y., Liang, C., Sun, Q. et al. Hydrolysis time-controlled pore and defect engineering in nanocellulose-derived biochar for enhanced ethylene glycol sensing. Biochar8, 110 (2026).
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
Credit: Fanchao Xu, Jun Zhu, Kun Liu, Minli Wang, Huiting Liu, Jianjun Lian, Xiaolei Qu & Bingyu Wang
Dissolved black carbon, a water-soluble fraction of black carbon produced from incomplete combustion and biochar, has long been viewed as a mobile form of carbon that can move from soils into rivers, lakes, estuaries, and oceans. A new review published in Biocharshows that its journey through the environment is far more complex than simple transport in water.
The review, titled “Colloidal stability of dissolved black carbon: interfacial mechanisms and environmental implications,” examines how dissolved black carbon, or DBC, behaves as a colloidal material. Its stability determines whether it remains suspended in water, aggregates into larger particles, or deposits into sediments. These processes directly influence not only the fate of DBC itself, but also the movement of pollutants that attach to it.
“Dissolved black carbon is not just a passive carbon residue in aquatic environments,” said the study authors. “Its colloidal behavior can decide whether carbon and associated contaminants travel long distances or become trapped in sediments. Understanding this behavior is essential for predicting environmental risks and carbon cycling.”
DBC is widely distributed in natural waters and is released from black carbon residues through leaching and surface runoff. Because it contains aromatic structures and oxygen-containing functional groups, DBC can bind with heavy metals, organic pollutants, antibiotics, and even nanoplastics. When DBC remains stable in water, it can act as a carrier that helps these substances move through aquatic systems. When it aggregates and settles, it can shift pollutants from the water column into sediments, creating localized contamination hotspots and changing exposure risks for benthic organisms.
The review highlights that DBC stability is governed by its molecular structure and surface chemistry, which depend on feedstock source, pyrolysis conditions, extraction conditions, and environmental aging. Using classical DLVO theory and extended XDLVO theory, the authors explain how electrostatic forces, van der Waals attraction, and Lewis acid-base interactions control DBC aggregation. The review notes that short-range acid-base interactions, especially hydration and hydrophobic forces, can be especially important in determining whether DBC remains dispersed or aggregates.
Environmental conditions can strongly alter this balance. Monovalent ions such as sodium often have limited effects, while divalent cations such as calcium, barium, and some heavy metals can destabilize DBC by binding with oxygen-containing groups and promoting particle bridging. pH also matters. Acidic conditions can reduce surface charge and encourage aggregation, while alkaline conditions often improve colloidal stability. Organic substances, minerals, and photoaging can either stabilize or destabilize DBC depending on their interactions with DBC surfaces.
These findings have important implications for water quality, soil remediation, and climate research. Biochar is widely studied as a soil amendment for carbon sequestration and pollutant immobilization, but DBC released from biochar may carry adsorbed pollutants away from treated soils under certain conditions. At the same time, aggregation and deposition of DBC in estuaries may remove a fraction of land-derived carbon before it reaches the ocean, meaning current estimates of land-to-ocean black carbon flux may need refinement.
“The colloidal stability of dissolved black carbon is a missing link between molecular carbon chemistry and large-scale environmental outcomes,” the authors said. “Future models of pollutant transport and carbon flux should account for how DBC aggregates, deposits, and interacts with coexisting substances in real environmental waters.”
The authors call for integrated characterization methods, stronger mechanistic studies of heteroaggregation in complex waters, and predictive models that combine molecular information with environmental parameters. Such efforts could improve risk assessment, water treatment strategies, and estimates of how black carbon contributes to long-term carbon storage.
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Journal Reference: Xu, F., Zhu, J., Liu, K. et al. Colloidal stability of dissolved black carbon: interfacial mechanisms and environmental implications. Biochar8, 108 (2026).
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
The EU must reduce its greenhouse gas emissions by 90 percent by 2040 relative to 1990 – of which 5 percentage points can be achieved through climate action elsewhere, according to the 2025 law. A study by the Potsdam Institute for Climate Impact Research (PIK) now proposes a novel instrument for this external component: performance-based Jurisdictional Reward Funds. This avoids perverse incentives, strengthens international and thus also European climate action, and costs just 5 billion euros annually. The study is available as a PIK Policy Paper on the institute’s website. Co-author Ottmar Edenhofer is PIK Director and Chair of the EU climate advisory board.
“Our analysis shows that the international flexibility built into the EU’s 2040 climate target should not simply be dismissed as a questionable substitute for political ambition at home,” says Edenhofer. “Rather, climate protection beyond our borders acts as a stabilising mechanism. It ensures that ambitious climate policy in Brussels remains realistic in the future – regardless of what is decided in Beijing or Washington.”
This two-part climate target refers to a somewhat controversial provision in the Paris world climate agreement: a country can acquire “international carbon credits” and count them towards its own climate balance by financing emissions reductions abroad, either at the project or the government level. Some see this as a gateway to cheating. After all, there is little additional benefit to financing climate protection projects if they were planned anyway. And at government level, funding may create incentives for countries to initially set their targets too low in order to be excessively rewarded later. However, both problems can be overcome.
Just 21 euros per tonne of CO₂ saved.
“The option of crediting climate protection efforts beyond one’s own borders is an opportunity – if it is designed correctly,” says Lennart Stern, PIK researcher and also an author of the study. “To avoid the perverse incentives of previous voluntary carbon markets, we propose a more efficient framework: Brussels would provide financing via so-called Jurisdictional Reward Funds as remuneration for efforts made by governments outside the EU. All developing and emerging economies with a proven track record of tightening climate policy would be eligible. The key point is that, in principle, the offer is the same for all countries.”
Such a performance-based reward could, for example, promote forest conservation in non-EU countries. It would then reallocate a fixed budget year on year to countries that have been particularly successful, measured against a universally set deforestation rate. Each country would know in advance the level of performance required to receive funding; the amount of the payment would then depend on how much the country is doing compared to other countries. The formula is designed in such a way that above-average and additional efforts are rewarded with higher payments.
The research team also provides an initial estimate of the costs involved. This is based on early experiences with the rainforest fund launched at the most recent world climate summit, as well as on empirical research into fossil fuel markets. In the cost-optimal mix, the EU would allocate only 6 percent of this new policy instrument to forest conservation, 32 percent to phasing out oil and gas, and 62 percent to phasing out coal. Reducing greenhouse gases beyond its borders by 5 percent relative to 1990 EU levels would then cost the EU 5 billion euros in 2040. That is just 21 euros per tonne of CO₂ avoided.
Automatic alignment with what China and the US are doing
Climate protection achieved abroad also has benefits for the EU itself. The international carbon credits received under the Paris Agreement can be integrated into the EU Emissions Trading System (ETS), where they can help prevent sharp price rises. The study calculates that, through the gradual introduction of international carbon credits between 2036 and 2050, the carbon price in the existing EU ETS covering electricity and energy-intensive industry could be 40 to 45 percent lower, on average, than without these credits. The incentive to move away from fossil fuels remains strong – because investors expect carbon prices to rise outside Europe due to increased climate cooperation.
Under current conditions, Brussels can achieve significant emission reductions using the policy instrument outlined in the study. After all, there are still many cost-effective abatement opportunities in developing and emerging economies. If, however, China and perhaps even the US were to use such reward funds at any point in the future, this potential for low-cost emission reductions would soon be exhausted. Costs would rise, and more of the EU’s 2040 climate target would have to be achieved within the EU itself. But in this case, Europe would be less exposed with its climate policy, and global climate protection would be strengthened even more.
At first glance, it looks like a simple calculation. The state offers compensation. The climate demands action. Low-lying soils must be restored as wetlands. Yet landowners hesitate. According to anthropologist and PhD student Kasper Krabbe from the Department of Agroecology at Aarhus University, that is exactly where the misunderstanding begins.
“Of course, the size of the financial compensation matters. But our study shows that it cannot stand alone if we want to understand why landowners say yes or no,” he says.
Together with colleagues from Aarhus University and the University of Copenhagen, he has investigated why some Danish landowners decline to convert their land, even when compensation is readily available.
The results point to a tension between what is easiest to design policy around, economic compensation, and what is hardest to formalize: responsibility, uncertainty, professional pride, and attachment to the land.
A landscape of values
Imagine a farmer standing at the edge of a field. This is where it all begins: with a gaze across the land and reflections on what the future holds. Should the land be flooded again? What will happen to the neighboring fields? To the value of the farm? To the next generation?
“For many, this is not just about production. The land is part of their life story,” says Kasper Krabbe.
The study, based on 14 in-depth interviews with landowners, paints a picture of decisions woven together from economics, ethics, identity, and everyday practices. The land is not just a resource. It is heritage. It is responsibility. It is emotion.
“There is a strong sense of obligation both to the family and to the landscape,” says Kasper Krabbe.
The idea of the ‘good farmer’
There are also more implicit norms: ideas about the “good farmer.” A concept the researchers use to describe the unwritten rules of farming, how a field should look and what counts as proper work.
“You are also judged by your neighbours,” as Kasper Krabbe puts it. “The way fields look sends signals about who you are.”
From this perspective, a wet field left untouched can be difficult to reconcile with the ideal of efficient farming. This is not necessarily an argument against nature restoration, but it makes the decision more complex.
At the same time, there are practical considerations. The schemes are voluntary, and although they are financially compensated, they are also associated with uncertainty. What if the regulations change? What if the project affects the rest of the farm? And what about all the administrative requirements?
“There is a perception that it is complex and risky,” says Kasper Krabbe.
For some, it simply becomes too difficult to grasp.
When policy meets reality
Denmark has ambitious plans to retire low-lying agricultural soils as a tool in climate and nature policy. But even when schemes are voluntary and compensated, the decision is rarely simple for individual landowners.
The study highlights a key challenge: many schemes are, understandably, built around financial incentives because they are relatively easy to administer and communicate. However, landowners’ decisions are also shaped by professional pride, local relationships, concerns about the future, and ideas about what it means to take good care of one’s land.
“There is a mismatch between how the schemes are designed and how farmers actually think,” says Kasper Krabbe.
If more landowners are to say yes, it is not just about increasing compensation. It is also about making participation more professionally and socially meaningful.
One option is to more clearly link the schemes to recognition of good farming practice, so that restoring wetlands is not framed as giving up the land, but as another way of taking responsibility for the landscape. Another option is to strengthen the advisory environments that landowners already use and trust.
“We need to take non-economic values more seriously,” says Kasper Krabbe. “Otherwise, we miss the mark.”
More than climate policy
The discussion of low-lying soils is ultimately about something bigger. It concerns how society tries to change practices, and what happens when people do not fit into the models.
“If we want to succeed with the green transition, we need to understand the people who have to carry it out,” says Kasper Krabbe.
In the end, it is not the state that converts the land, but the landowners themselves, who must make present and future align. The study also points to advisory services as a key factor.
“Many landowners seek advice from consultants they already know. If those advisors do not have a clear role in the lowland initiatives, an important bridge between the schemes and the individual farm is lost,” says Kasper Krabbe.
More Information
Collaborators: Department of Agroecology at Aarhus University and Department of Food and Resource Economics at the University of Copenhagen.
Funding: Co-funded by the European Union through the SoilValues project (grant agreement no. 101091308), which partially funds Kasper Krabbe’s PhD. Open access is funded by Aarhus University.
Bee species that nest in plant stems appear to be at the greatest short-term risk from increasing temperatures due to climate change, while those that nest in the ground are more able to evade extreme heat, according to new research from Australian evolutionary ecologists.
The study, published today in the international journal Nature Communications (link), assessed heat tolerance in 95 different native bee species in eastern mainland Australia, at all latitudes from north to south.
Researchers from Macquarie University, The University of Sydney, La Trobe University, Flinders University, University of Wollongong, Adelaide University and The University of Queensland investigated the way tolerance to heat has evolved across diverse bee species and compared their sensitivity to climate change.
Australian native bees – of which there are some 1700 species – have three main nesting behaviours: some nest in burrows in the ground, some in wood cavities like tree hollows or fallen dead branches, and others in plant stems or existing holes in small twigs.
“Bees that nest underground can hide from extreme heat – as a result, they don’t experience temperatures as high as those that live above ground, particularly species that live in thin plant stems that offer very little insulation from the heat outside,” says lead author Dr Carmen da Silva, a Research Fellow in the Pollinator Futures Research Centre at Macquarie University in Sydney.
“Stem-nesting species appear to have the lowest capacity to escape unfavourable environmental temperatures and are likely to be the most impacted by anthropogenic climate change in the near term.”
“Bees are critical in ecosystems all over the world because of their role as pollinators, and they’re under threat from warming and drying climates,” says Dr da Silva. “Bees sustain native ecosystems and play a crucial role in agricultural crop production – tropical native bees are vital pollinators for crops like macadamia nuts, avocados, mangos and lychees.”
Dr Vanessa Kellermann, Senior Lecturer in the Department of Ecology, Plant and Animal Sciences at La Trobe University, says the research also found a clear trend for increasing vulnerability to climate change closer to the equator, with tropical bees at the greatest risk.
“Predicting which species will be vulnerable to climate change is one of the biggest challenges in ecology,” says Dr Kellermann, a senior author of the study. “We found bee species with the highest heat tolerance were not necessarily the safest from warming, because many of them already live in extremely hot environments."
“We still know so little about most of Australia’s amazing native bees,” says co-senior author Dr Ros Gloag, Senior Lecturer in Evolutionary Biology in the School of Life and Environmental Sciences at the University of Sydney. “This study helps us recognise that having a better understanding of native bee behaviour is key to identifying the greatest threats to their wild populations.”
