Microalgae and green catalysts: paving the way for eco-friendly metal cluster synthesis
|Metal clusters — small assemblies of metal atoms — are central to many modern technologies. However, their traditional chemical synthesis relies on toxic solvents and high energy input. A greener alternative is needed, and a help can come from nature: in particular, from microalgae, tiny photosynthetic organisms that naturally absorb and organize metals as part of their metabolism.
PhD student Marija Tanovic and Dr Milan Zizic (University of Belgrade) and colleagues studied the effectiveness of a microalga, C. sorokiniana, in processing the Mn, discovering that it can synthesize and accumulate a multivalent Mn–O cluster when exposed to manganese under specific conditions. Using synchrotron-based spectroscopy, they found out the cluster’s structure closely resembles the tetramanganese cluster in the photosynthetic Oxygen-Evolving Complex, which is responsible for splitting water into oxygen. Moreover, by 31P NMR spectroscopy performed at the NMR spectrometer ORO available at the Slovenian Partner Facility at the National Institute of Chemistry (Ljubljana), they described the interactions of paramagnetic Mn2+. Scientists found out that the Mn–O cluster is paramagnetic at room temperature, catalytically active, and extractable — with a biosynthetic yield of about 25%. The cluster’s dual magnetic and catalytic behaviour could then enable easy recovery and reuse in industrial processes, a major advantage for sustainable catalysis.
These outcomes make C. sorokiniana the first known microalga capable of producing such a complex, biologically inspired structure, paving the way to green metal cluster synthesis, but also to artificial photosynthesis and pollutant degradation (potentially allowing to break down harmful compounds in water and soil).
ORIGINAL ARTICLE:
-
14.11.2024 | Catalysis, Energy
New insights on catalytic nanoparticles synthesis