Related Experiment Video
Updated: Dec 10, 2025
10:21
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
8.8K
Sonochemical Hydrogen Production as a Potential Interference in Light-Driven Hydrogen Evolution Catalysis.
Isolda Roger1, Sven Rau1, Carsten Streb1
1Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
ACS Omega
|September 3, 2020
Summary
Ultrasonic baths can initiate unintended hydrogen evolution during photocatalyst dispersion, interfering with light-driven hydrogen evolution studies. This dark hydrogen evolution persists after sonication, potentially skewing research results.
Area of Science:
- Materials Science
- Photocatalysis
- Energy Conversion
Background:
- Sonication is widely used to disperse solids in solvents for catalytic research.
- Commercial ultrasonic baths can induce unintended sonochemical reactions.
- These reactions can interfere with sensitive experimental measurements.
Purpose of the Study:
- To investigate the potential for sonication to cause non-photochemical hydrogen evolution.
- To highlight the interference of sonication-induced hydrogen evolution in photocatalytic studies.
- To alert the research community to a potential source of error in hydrogen evolution experiments.
Main Methods:
- Dispersing heterogeneous photocatalysts in water-alcohol mixtures using sonication.
- Monitoring hydrogen evolution during and after sonication in the absence of light.
- Analyzing the source of hydrogen evolution unrelated to photocatalysis.
Main Results:
- Sonication of photocatalysts in water-alcohol mixtures directly led to hydrogen evolution.
- This 'dark' hydrogen evolution continued even after sonication was stopped.
- The observed hydrogen evolution was not linked to photochemical or photocatalytic processes.
Conclusions:
- Sonication itself can be a source of hydrogen evolution, independent of light or photocatalysis.
- This phenomenon poses a significant challenge for accurate time-dependent hydrogen evolution studies.
- Researchers in energy conversion must account for sonication-induced hydrogen evolution to avoid experimental errors.
Related Concept Videos
02:13Reduction of Alkenes: Catalytic Hydrogenation
13.7K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
13.7K
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.7K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.7K
02:50Catalysis
29.7K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
29.7K
01:34The Z-Scheme of Electron Transport in Photosynthesis
12.5K
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
12.5K
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
5.5K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
5.5K
01:32Chemiosmosis
110.0K
Oxidative phosphorylation is a highly efficient process that generates large amounts of adenosine triphosphate (ATP), the basic unit of energy that drives many cellular processes. Oxidative phosphorylation involves two processes— the electron transport chain and chemiosmosis.
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
110.0K