Catalysis is the process of increasing the rate of a chemical reaction by adding a substance, known as a catalyst, which is not consumed by the reaction itself. Catalysts function by providing an alternative reaction pathway with a lower activation energy, allowing molecular collisions to reach the transition state more easily,. They are classified into three primary categories:

• Heterogeneous: The catalyst and reactants exist in different phases (e.g., solid catalysts with gas or liquid reactants).

• Homogeneous: The catalyst and reactants are in the same phase.

• Biocatalysis: Utilizes natural proteins (enzymes) or nucleic acids to catalyze reactions with high selectivity and mild conditions,.

Industrial Significance

Catalysis is the "silent engine" of the global economy; approximately 90% of all commercially produced chemical products involve catalysts at some stage of manufacture.

• Food Security: The Haber-Bosch process uses iron-based catalysts to convert nitrogen and hydrogen into ammonia for fertilizers, sustaining food production for roughly 40% of the global population.

• Polymers: Ziegler-Natta catalysts revolutionized the production of stereoregular polymers (plastics) like polypropylene, acting as microscopic assembly lines,.

• Pharmaceuticals: Biocatalysis is increasingly preferred for synthesizing active pharmaceutical ingredients (APIs) because enzymes offer exquisite regio- and stereoselectivity, reducing the need for toxic reagents and complex protection steps common in traditional chemocatalysis,.

Modern Innovations and Future Trends

The field is currently undergoing a transformation from empirical "trial-and-error" methods to rational, data-driven design,.

1. Artificial Intelligence (AI): AI and machine learning are accelerating catalyst discovery. Tools like GNoME have identified millions of new stable crystals, while Large Language Models (LLMs) like Catal-GPT interact with researchers to optimize catalyst formulations and extract knowledge from vast scientific literature,.

2. High-Entropy Alloys (HEAs): In electrocatalysis, HEAs combine five or more elements to create highly stable and tunable surfaces. These are showing superior performance in renewable energy applications, such as the Hydrogen Evolution Reaction (HER) and Oxygen Reduction Reaction (ORR), overcoming the durability limitations of traditional noble-metal catalysts,.

3. Sustainability & Circular Economy:

◦ Plastic Upcycling: Catalysts are essential for chemically recycling waste polymers, using techniques like catalytic pyrolysis and hydrogenolysis to convert plastics back into monomers or fuels rather than downcycling them,.

◦ Carbon Capture (CCS): Advanced solvents (e.g., amines, enzymes) and solid sorbents are being deployed to capture CO₂ from industrial flue gases to meet net-zero targets,,.

◦ Small Modular Reactors (SMRs): SMRs are being integrated to provide the massive amounts of clean, high-temperature heat and electricity required for industrial catalytic processes, such as hydrogen and synthetic fuel production