Hafnium is a chemical element with symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1923, making it the penultimate stable element to be discovered (rhenium was identified two years later).
Three reasons Hafnium stands out
- 1
Used in nuclear reactors due to its high neutron absorption.
- 2
Intel introduced transistors using this element's oxide in 2007, marking one of the biggest breakthroughs in chip design in decades.
- 3
It was the last stable element to be discovered, finally identified in 1923 after a long scientific search.
The neutron catcher beside zirconium
Hafnium accompanies zirconium in nature because their atoms are nearly the same size, making separation unusually difficult. Their nuclear behavior is opposite: hafnium absorbs neutrons strongly. That makes it useful in reactor control systems, while hafnium oxide became crucial in shrinking modern computer transistors.