Science Daily February 15, 2024 Electric fields play a key role in enzymatic catalysis and can enhance reaction rates by 100,000-fold, but the same rate enhancements have yet to be achieved in thermochemical heterogeneous catalysis. Researchers at MIT probed the influence of catalyst potential and interfacial electric fields on heterogeneous Brønsted acid catalysis. They found that variations in applied potential of ~380 mV led to a 100,000-fold rate enhancement for 1-methylcyclopentanol dehydration, which was catalyzed by carbon-supported phosphotungstic acid. Mechanistic studies supported a model in which the interfacial electrostatic potential drop drove quasi-equilibrated proton transfer to the adsorbed substrate prior […]
Category Archives: Catalyst
Atomically dispersed bimetallic iron–cobalt electrocatalysts developed for green production of ammonia
Phys.org November 14, 2022 Electrosynthesis of ammonia from nitrogen reduction reaction (NRR) at ambient conditions has been widely regarded as a green ammonia synthesis technology to replace the traditional energy- and capital-intensive Haber-Bosch process. Although single-atom electrocatalysts (SACs) may create a new catalytic paradigm, one of the key challenges hindering the rational design and development of SACs is the lack of insight into the relationship between performance and SA loading. An international team of researchers (China, Australia) demonstrated an adsorption-regulated synthetic method that uses bacterial cellulose as an adsorption regulator to control Fe3+/Co2+ impregnation on bacterial cellulose through carbothermal reduction. […]
Energy researchers invent chameleon metal that acts like many others
Phys.org May 9, 2022 A team of researchers in the US (University of Minnesota, UMass Amherst, UC Santa Barbara) has invented a device called catalytic condenser that allowed them to tune the number of electrons at the surface of the catalyst converting one metal to behave like another. They fabricated the catalytic condenser by combining nano-scale film of alumina with graphene, which could be electronically tuned. The condenser uses a combination of nanometer films to move and stabilize electrons at the surface of the catalyst. The power of the device to stabilize electrons is tunable with varying composition of a […]
New approach creates an exceptional single-atom catalyst for water splitting
Phys.org September 1, 2021 Electrolysis could produce fuels and chemical feedstocks more sustainably and reduce the use of fossil fuels. But the sluggish pace of oxygen evolution reaction (OER) has been a bottleneck to improving its efficiency. A team of researchers in the US (Stanford University SLAC National Accelerator Laboratory, Lawrence Berkeley National Laboratory, UC Berkeley, NIST) used operando X-ray absorption spectroscopy measurements to demonstrate that the origin of water oxidation activity of IrNiFe SACs is the presence of highly oxidized Ir single atom in the NiFe oxyhydroxide under operating conditions. They showed that the optimal water oxidation catalyst could […]
Single atoms as catalysts
Nanowerk September 2, 2019 Researchers in Austria have shown that metal atoms can be placed on a metal oxide surface so that they show exactly the desired chemical behavior. When metal atoms are deposited on a metal oxide surface, they usually have a very strong tendency to clump together and form nanoparticles. Instead of attaching the active metal atoms to a surface, it is also possible to incorporate them into a molecule with cleverly selected neighboring atoms. The molecules and reactants are then dissolved into a liquid where the chemical reactions take place. They have developed a technique to incorporate […]