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Catalytic converters (automotive catalysts) and the chemical reactions they catalyze appear in general and introductory chemistry textbooks. Although the detailed mechanisms of the chemical reactions that occur in catalytic converters have been clearly revealed via recent developments in surface and computational chemistry research, the description and illustration of the catalysis are still ambiguous in textbooks. In this paper, we describe an extracurricular lecture whereby a handmade teaching aid was employed to illustrate the basic principle of the catalytic oxidation of carbon monoxide over platinum surface, which is an essential reaction occurring in catalytic converters. The teaching aid, constructed combining easily available materials, can illustrate the positions and motions of the molecules on the platinum surface during catalytic oxidation. The lecture was favorably received by non-chemistry majors and high school students. Despite the difficulty of the topic, the audience displayed a relatively high level of understanding.

Structure model sets for inorganic compounds are generally expensive; their distribution to all students in a class is therefore usually impractical. We have therefore developed a structure model set to illustrate inorganic compounds. The set is constructed with inexpensive materials: ping-pong balls, and snap buttons. The structure model set can be used to illustrate isomerism in coordination compounds and periodic structures of ceramic perovskites. A hands-on activity using the structure model set was developed for high school students and was well-received by them. Despite the concepts being slightly advanced for them, the students’ retention of the knowledge gained through the activity was tested a week after they completed the activity and was found to be relatively high, demonstrating the usefulness of the activity based on the structure model set.

Co3Mo3N has been reported to have activity for the synthesis of ammonia surpassing that of industrial Fe catalysts under certain conditions. However, so far the research has largely focused on unsupported Co3Mo3N. We report a comprehensive study on the catalytic activity of Co3Mo3N when supported on two distinct MgO substrates. Our findings reveal that the method of MgO preparation plays a crucial role in influencing surface basicity. Remarkably, Co3Mo3N supported on single‐crystalline MgO demonstrates significantly enhanced catalytic activity, achieving a 162.0 mmol g−1metal h−1 rate. This surpasses the performance on commercial MgO support (41.2 mmol g−1metal h−1) and unsupported Co3Mo3N (15.0 mmol g−1metal h−1). While kinetic analyses show no substantial differences between the two supported catalysts, spectroscopic studies employing CO2 and N2 temperature‐programmed desorption (TPD) reveal a richer array of basic sites and adsorption/desorption phenomena on the single‐crystalline MgO support. These catalysts exhibit exceptional stability. The drastically reduced Co/Mo loading amounts in comparison to the bulk form, make the commercialization of Co3Mo3N catalysts more practical. [ABSTRACT FROM AUTHOR]

A unique demonstration with ball-rolling mechanisms has been developed to illustrate the basic principles of mass analyzers as components of mass spectrometers. Three ball-rolling mechanisms mimicking the currently used mass analyzers (i.e., a quadrupole mass filter, a magnetic sector, and a time-of- flight) have been constructed. Each mechanism was designed to separate balls with three different weights (representing three ionized analytes with different weights) in an attempt to imitate the separation process employed by real mass analyzers. This demonstration helped students understand the basic principles of mass analyzers.

We describe an activity that is suitable for high school students and makes use of plastic bottles. This activity allows students to familiarize themselves with gas chemistry by introducing technologies that were applied in old submarine systems. Plastic bottles, which are representative of submarines, are used as reaction vessels. Three simple experiments regarding gas chemistry are carried out in the plastic bottles: (1) a carbon dioxide absorption reaction using soda lime, which mimics an air-cleaning canister; (2) a chlorine and hydrogen evolution reaction by the electrolysis of brine, which highlights the accidental generation of gases by lead batteries on board submarines; and (3) a catalytic hydrogen peroxide decomposition that exists in submarine propulsion system. To introduce an antisonar countermeasure system outside the submarine, a fourth experiment on hydrogen generation by the reaction of calcium hydride and water is also conducted.

Typically, transition metals are considered as the centers for the activation of dinitrogen. Here we demonstrate that the nitride hydride compound Ca3CrN3H, with robust ammonia synthesis activity, can activate dinitrogen through active sites where calcium provides the primary coordination environment. DFT calculations also reveal that an associative mechanism is favorable, distinct from the dissociative mechanism found in traditional Ru or Fe catalysts. This work shows the potential of alkaline earth metal hydride catalysts and other related 1 D hydride/electrides for ammonia synthesis. [ABSTRACT FROM AUTHOR]

Catalysis with transition-metal complexes is a part of the inorganic chemistry curriculum and a challenging topic for upper-level undergraduate and graduate students. A hands-on teaching aid has been developed for use during conventional lectures to help students understand these catalytic reactions. A unique method of illustrating the coordination polymerization of propylene with interlocking building blocks is described. Three metallocene block models mimicking real catalysts recognize top and bottom faces of a prochiral propylene monomer block model and subsequently provide three polypropylene structures with different tacticity. The monomer recognition processes of the metallocene block models are based on steric hindrance, similar to those of the real catalysts. (Contains 4 figures.)

Layered bismuth oxyhalides with bilayered (Bi2O2) fluorite (FL) slabs are promising visible‐light photocatalysts because of their excellent stability and the ability to adjust band levels depending on the layers combined. It is interesting to manipulate the Bi2O2 slab itself, but only trilayered FL blocks (e.g., Bi3O4) are reported so far. Here, a structurally uncharacterized Bi12O17Cl2, which is extensively studied as a photocatalyst for a variety of reactions, has a sextuple Bi6O8.5 block separated by Cl is shown. Unlike double and triple layered cases, the inner region of the Bi6O8.5 block contains 1D rock‐salt (RS) units in the FL matrix along the a‐axis, causing in‐plane corrugation. A topochemical reaction involving anion‐exchange gives Bi12O17–0.5xFxCl2 (x ≤ 6) with alternate FL and RS slabs along the c‐axis. The elimination of the structural corrugation increases higher photo‐conductivity and improves photocatalytic activity against acetic acid decomposition under visible light irradiation. This study paves new opportunities of controlling the properties of layered bismuth oxyhalides by the thickness of Bi–O block, FL/RS configuration, and structural modulation. [ABSTRACT FROM AUTHOR]

Topochemical reactions have led to great progress in the discovery of new metastable compounds with novel chemical and physical properties. With these reactions, the overall crystal structure of the host material is generally maintained. Here we report a topochemical synthesis of a hexagonal nitride hydride, h‐Ca3CrN3H, by heating an orthorhombic nitride, o‐Ca3CrN3, under hydrogen at 673 K, accompanied by a rotational structural transformation. The hydrogen intercalation modifies the Ca−N rock‐salt‐like atomic packing in o‐Ca3CrN3 to a face‐sharing octahedral chain in h‐Ca3CrN3H, mimicking a "hinged tessellation" movement. In addition, the h‐Ca3CrN3H exhibited stable ammonia synthesis activity when used as a catalyst. [ABSTRACT FROM AUTHOR]