Theory of

HER

INTRODUCTION

Carbon dioxide was initially more important than dangerous because the Earth's natural greenhouse effect preserved the average global surface temperature above freezing. Humans, on the other hand, are greatly influencing the natural greenhouse effect by adding more carbon dioxide to the atmosphere, causing global temperatures to rise rapidly.

Since the 18th century (the Industrial Revolution), human activities have raised atmospheric CO2 levels by 50% – meaning the amount of CO2 is now 150% of the value since the mid-18th century. This rise is greater than the natural increase observed at the end of the last ice age 20,000 years ago.

Source: https://ourworldindata.org/co2-emissions

Source: https://www.aeologic.com/blog/role-of-hydrogen-fuel-cells-in-global-energy-system/

Scientists are putting in relentless effort to meet energy needs in environmentally friendly ways, showcasing the potential of diverse alternative energy options like solar and wind power, as well as energy storage technologies such as metal-air batteries and hydrogen evolution reactions (HER). Hydrogen is the most abundant element on earth and can potentially replace hydrocarbon-based transportation fuels. Hydrogen is the most abundant element in our environment and even our universe. It is found in water (H2O) and has the potential to replace hydrocarbon-based transportation fuels. A major limitation of using hydrogen as a fuel is efficient extraction.

Advanced cathodes capable of turning all electrical energy into hydrogen are required for efficient electrolysis hydrogen generation. Platinum has been proven to be the most efficient metal for hydrogen evolution in several investigations. Platinum, on the other hand, is a costly metal. Scientists are working to develop low-cost cathodes using transition metals to solve this challenge.

Source: https://www.istockphoto.com/vector/water-electrolysis-process-scientific-chemistry-diagram-vector-illustration-gm946287008-258427824

In the field of catalysts, surface modifications are crucial for enhancing catalytic activity, selectivity, and stability. Catalysts are substances that facilitate chemical reactions by lowering the activation energy required for the reaction to occur. Modifying the surface of catalyst materials is often done to improve their performance. Metal surfaces are changed to improve the efficiency of low-cost metals. Surface activity may be increased in a variety of methods, including the formation of nanostructures on the surface, doping, modifying the microstructure, and so on.

The preceding images demonstrate how the activity of transition metals improves as the surface is changed. The curve of potential versus current density in the second image demonstrates that transition metals may obtain overpotentials equivalent to platinum by modifying the surface or generating aggregate compounds.