The ternary combination of metal cations, CuI and viologen based carboxylate leads to two donor-acceptor hybrid heterostructures with novel cuprous iodide clusters and narrow energy gaps. Thanks to the facilitated electron transfers between both donor and acceptor components, these unique hybrids exhibit enhanced photocatalytic degradation activities towards organic dyes under visible light irradiation in comparison with those of bulk CuI and viologen semiconductors.