LEDs: New Lamps for Old and a Paradigm for Ongoing Curriculum Modernization

Abstract

Advances in science and technology afford new opportunities for enriching and updating the chemistry curriculum by connecting such developments and their products to core chemical principles. This article illustrates this approach to curriculum modernization using advances in lighting and display technologies with light-emitting diodes (LEDs). As noted in an industry summary, an excellent resource for this topic, LEDs are replacing traditional incandescent sources in many lighting and display technologies for reasons of energy efficiency, safety, and conservation. Their widespread use in vehicle, traffic, display, home, and workplace lighting provides opportunities to directly engage students' interest. The chemistry underpinning LEDs spans many core chemistry curriculum topics, because the semiconductors in the light sources comprise a family of essentially isostructural solids that embrace a variety of periodic trends. Bonding trends exemplified by the solids include electronegativity, atomic radii, bond polarity, isoelectronic principles, and spectroscopic transitions. The solids also provide an acid-base and concentration cell system that complements traditional presentations of aqueous systems. At a more advanced level, the quantum mechanics of spatially confined particles can be presented with this family of solids. This approach to curriculum modernization also affords opportunities to establish interdisciplinary links between chemistry and other scientific and engineering fields.

Improving Student Motivation and Perception of Chemistry’s Relevance by Learning about Semiconductors in a General Chemistry Course for Engineering Students

“…10,11 There is an increasing recognition that chemistry curricula can effectively incorporate examples from modern research and technology to communicate core chemical principles and demonstrate their societal relevance. 12 Nontraditional forms of content enable instructors to bridge chemistry with emerging fields, providing cross-disciplinary learning experiences. 4 The rapid advancements in semiconductor-related technologies make them ideal for incorporation into chemistry curricula as practical examples of chemical principles applied in cutting-edge research and technology.…”

“…4 The growing significance of semiconductors highlights their suitability for the application of chemical principles in electronic and optical devices, showcasing the interdisciplinary connections between chemistry and other fields. 12 However, there is a lack of research focused on communicating the core chemical principles of semiconductors to update curricula and establish connections between chemistry and other disciplines in general chemistry courses for engineering students.…”

“…The aim was to enhance students' motivation to learn and help them recognize the relevance of chemistry by emphasizing how the core chemical principles concerning semiconductors' composition and band gap connect a wealth of applications and technologies. 12 Guided by the relevance framework of science education, 5 the short course focused on the chemical aspects of semiconductors, along with their practical applications in electronic devices and everyday life. This approach aimed to enable students to appreciate the relevance of the course content more deeply.…”

Properties of Semiconductors: Synthesis of Oriented ZnO for Photoelectrochemistry and Photoremediation

“…Semiconductor electrical conduction occurs when electrons are excited across the band gap and electrons are then free to move to other orbitals of similar energy (Figure ). Semiconductor materials are important for light-emitting diodes , and solar energy conversion because their band gaps can occur in or close to the visible region of the spectrum.…”

Investigating Bandgap Energies, Materials, and Design of Light-Emitting Diodes

“…In this Journal , the earliest report on LEDs was by Gurnee back in 1969 . Since then, reports in this Journal have included demonstrations, emission correlation to bandgap of the diode, and general discussions of LED technology and how they are used in electronics . Physics education literature has focused on experiments created and designed to measure the bandgap of diodes. − Precker has also reported on a method to relate bandgap energy of the LED to the wavelength of emission .…”