Without getting you mired in technobabble, let's just say that indium tin oxide (ITO) has generally been a mainstay in every single OLED that was produced commercially.

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And, as a bonus, tin oxide is harmless.

ECONOMIST: The Romans, too, had sophisticated cosmetics

Tests have shown Cambrios material beats the best known material used today called indium-tin-oxide, or ITO, and costs less.

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The metal in question is tin, and an oxide of that metal was one of the main ingredients of the cosmetic.

ECONOMIST: The Romans, too, had sophisticated cosmetics

Metallic tin is not electropositive enough compared with the electronegativity of its oxide to deliver a useful potential difference.

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