Do copper infused socks really help control foot odor?
Copper is antibacterial and anti-fungal. So is silver. Many metals (and metal salts) are potentially antimicrobial. Silver and copper are fairly benign to human skin, so these are widely used; you wouldn't want arsenic or antimony in your socks.
The attachment of the metal nano- or micro-particles to the fabric is critical. Merely soaking your socks in copper sulfate will not sustain the anti-odor effect; it will wash out when you launder the socks. Although you could spray a copper solution on your feet or inside-out socks before putting them on.