The above listed constraints, when considered simultaneously, identify crystalline
ZnS as the single compound that (i) can serve as an efficient photocatalyst
capable of reducing CO2 with a quantum yield of up to 80%, (ii) can promptly
absorb UV quanta from the adsorbed organic compounds, preventing their destruction,
and (iii) is a major constituent of hydrothermal vent systems, being
typically found at their outer surface and/or periphery.