We compute the decay rates of emitters coupled to spheroidal nanoantennas made of gold, copper,
silver, and aluminum. The spectral position of the localized surface plasmon-polariton resonance,
the enhancement factors and the quantum efficiency are investigated as a function of the aspect
ratio, background index and the metal composing the nanoantenna. While copper yields results
similar to gold, silver and aluminum exhibit different performances. Our results show that with a
careful choice of the parameters these nanoantennas can enhance emitters ranging from the UV
to the near-IR spectrum.