Gel-incorporated PbS and PbI₂ single-crystals

Gel-incorporated single-crystals provide unique combinational properties of long-range order and composite structures, which is desired for semiconducting and conducting materials. However, the reported gel-incorporated single-crystals are limited to insulating crystals. Here, we examine crystals of two typical semiconductors, lead sulfide (PbS) and lead iodide (PbI₂), grown from both silica gels and agarose gels. In all the four crystal-gel pairs, single-crystals of the cubic phase of PbS and the hexagonal phase of PbI₂ were obtained according to the X-ray diffraction analysis. Dissolution of the gel-grown crystals exposed insoluble materials with the shape similar to the original crystals, indicative of gel-incorporation inside the crystals. As such, this work creates a facile strategy to construct 3D heterostructures inside semiconducting single-crystals without destroying their long-range order.