Activation Energy in Photochemical and Thermally Driven Reactions: Mechanistic Insights, Kinetic Modelling and Photocatalytic Applications

Year : 2026 | Volume : 04 | Issue : 01 | Page : 21 26
    By

    Pushpa Mehdoo,

  • Meena Bandhan,

  • S. Ravichandran,

  1. Principal, PACIFIC School of Law, Udaipur, Rajasthan, India 2Research Scholar in Yogic Science, Manipur International University, Mount Abu, Rajasthan, India
  2. Research Scholar in Yogic Science, Manipur International University, Mount Abu, Rajasthan, India
  3. Professor in Chemistry, Tagore Institute of Engineering and Technology, Salem, Tamil Nadu, India

Abstract

Chemical reactions constitute fundamental processes in which reactants are transformed into products through the breaking and formation of chemical bonds. In photochemical systems, these transformations are initiated or influenced by the absorption of light, making energy transfer mechanisms particularly significant. A key parameter governing reaction kinetics is activation energy, defined as the minimum energy required for reactant molecules to undergo a successful transformation. This article focuses on the role of activation energy within the context of photochemical and photophysical processes. It discusses various types of chemical reactions with particular emphasis on light-induced reactions, where photons act as the primary energy source to overcome activation barriers. The influence of external factors such as light intensity, wavelength, temperature, and reactant concentration on activation energy and reaction rates is critically examined. Furthermore, the role of photocatalysts is highlighted, as they facilitate reactions by providing alternative pathways with reduced activation energy under light irradiation, without being consumed in the process. Such mechanisms are central to advancements in areas including solar energy conversion, environmental remediation, and photo-driven synthesis. Understanding activation energy in photochemical systems enables reaction conditions, thereby enhancing efficiency and sustainability in diverse applications ranging from green chemistry to biological photo processes.

Keywords: Photochemical processes, photoactivation energy, photoreaction kinetics, photocatalysis, excited-state energy barriers, molecular collision dynamics, temperature effects on photoreactions, photochemical reaction mechanisms, light-induced kinetics, photoenzymatic catalysis

[This article belongs to International Journal of Photochemistry and Photochemical Research ]

How to cite this article:
Pushpa Mehdoo, Meena Bandhan, S. Ravichandran. Activation Energy in Photochemical and Thermally Driven Reactions: Mechanistic Insights, Kinetic Modelling and Photocatalytic Applications. International Journal of Photochemistry and Photochemical Research. 2026; 04(01):21-26.
How to cite this URL:
Pushpa Mehdoo, Meena Bandhan, S. Ravichandran. Activation Energy in Photochemical and Thermally Driven Reactions: Mechanistic Insights, Kinetic Modelling and Photocatalytic Applications. International Journal of Photochemistry and Photochemical Research. 2026; 04(01):21-26. Available from: https://journals.stmjournals.com/ijppr/article=2026/view=247650


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Regular Issue Subscription Original Research
Volume 04
Issue 01
Received 20/04/2026
Accepted 23/04/2026
Published 10/05/2026
Publication Time 20 Days
17

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