Russian researchers have developed new fertilisers based on nanopowders of transition metals. In field trials on agricultural crops, harvests increased by more than a quarter, compared with conventional fertilisers.
Iron, cobalt and copper affect a plant’s level of resistance to pests and diseases. These microelements are typically introduced into the soil as soluble salts, but rain and irrigation can wash them away, requiring further applications. They also have potential to disrupt local ecosystems as they pass into the groundwater.
An irrigation system in Idaho, US. Image: Jeroen Komen@Wikimedia Commons
The team, led by the National University of Science and Technology (NUST) in Moscow, has developed a group of fertilisers that are applied as a powder to plant seeds, without losses to the soil or water systems. In this way, ‘the future plant is provided with a supply of necessary microelements at the stage of seeding,’ reports Alexander Gusev, head of the project at NUST’s Department of Functional Nanosystems.
‘[It’s] a one-seed treatment by a product containing the essential microelements in nanoform. These particles of transition metals – iron, copper, cobalt – have a powerful stimulating effect on plant growth in the initial growth phase.’
Gusev reports improved field germination and increased yields of 20-25%.
The main difficulty was to produce a powder from the nanoparticles, which tended to quickly stick together as aggregates, says Gusev – a problem they solved by using organic stabilisers and then subjecting the colloidal solutions to ultrasonic processing.
Gusev now wants to discvover how the new fertiliser acts in different soils, and in relation to different plant cultures. Its environmental safety also needs to be evaluated before widespread use, he adds.
But Steve McGrath, head of sustainable agricultural sciences at Rothamsted Research, is sceptical. Plants are adapted to take up ionic forms of these microelements, not nanoparticles, he says. ‘Also, seeds do not take up much micronutrients. Roots do that, and depending on the crop and specific nutrient, most uptake is near to the growing ends of the root, and throughout the growing season, when the seed and nearby roots are long gone.’
Critics are skeptical of the efficacy of the new kind of fertiliser. Image: Pexels
If there is an effect on crop yield, he thinks it is more likely to be due to the early antifungal and antibacterial effects of nanoparticles. ‘They have a large and highly reactive surface area and if they are next to membranes of pathogens when they react they generate free radicals that disrupt those membranes. So, in a soil that is particularly disease-infected, there may be some protection at the early seedling stage.’
Platinum is one of the most valuable metals in the world. Precious and pretty, it’s probably best known for jewelry – and that is almost certainly its oldest use. But its value has become far greater than its decorative ability; today, platinum powers the world. From agriculture to the oil markets, energy to healthcare, we use platinum far more than we realise.
1. Keep the car running
Platinum is needed to make fuel for transport. Image: Pixabay
Platinum catalysts are crucial in the process that converts naphtha into petrol, diesel, and jet-engine fuel, which are all vital to the global economy. The emissions from those petroleum fuels, however, can be toxic, and platinum is also crucial in the worldwide push to reduce them through automotive catalytic converters. In fact, 2% of global platinum use in 2016 was in converting petroleum and 41% went into reducing emissions – a circle of platinum use that’s more impressive than a ring.
2. Feed the world
Nitric acid is a by-product of platinum which is used in fertilisers. Image: Pixabay
Another vital global sector that makes use of platinum catalysts is agriculture. Without synthetic fertilisers, we would not be able to produce nearly as much food as we need. Nitric acid is essential for producing those fertilisers and platinum is essential for producing nitric acid. Since 90% of the gauzes required for nitric acid are platinum, we may need to use more of it as we try to meet the global food challenge.
3. Good for your health
A pacemaker. Image: Steven Fruitsmaak@Wikimedia Commons
Platinum is extremely hard wearing, non-corrosive, and highly biocompatible, making it an excellent material to protect medical implants from acid corrosion in the human body. It is commonly used in pacemakers and stents. It is also used in chemotherapy, where platinum-based chemotherapeutic agents are used to treat up to 50% of cancer patients.
4. The fuel is clean
In addition to powering the cars of the present and reducing their environmental impact, platinum might well be crucial to the future of transport in the form of fuel cells. Platinum catalysts convert hydrogen and oxygen into clean energy, with water the only by-product.
5. Rags to riches
The Spaniards invaded the Inca Empire, South America, in 1532. Painted by Juan B Lepiani. Image: MALI@Wikimedia Commons
Amazingly, despite all this, platinum was once considered worthless - at least in Europe. In fact, it was considered a nuisance by the Spanish when they first discovered it in South America - as a corruption in the alluvial deposits they were earnestly mining and they would quite literally throw it away. It wasn’t until the 1780s that the Spanish realised it might have some value.
Because platinum is essential to so many aspects of our economy, there are concerns about supply meeting demand – particularly as nearly 80% is currently mined in South Africa, which has seen its mining industry repeatedly crippled by strikes in recent years.
Two Rivers platinum mine, South Africa. Image: Wikimedia Commons
Some believe the solution to the issue of supply is space mining, arguing the metal could be found in asteroids.
Others, such as researchers at MIT, are working to create synthetic platinum, using more commonly found materials. Neither approach is guaranteed to work but, given our increasing dependence on this precious metal, we could be more reliant on their success than we realise.