Abstract: Compositions of the formula MX.sub.2 :Y, wherein MX.sub.2 is a layer type transition metal dichalcogenide, M is a metal selected from the group consisting of niobium, tantalum, molybdenum and tungsten, X is a chalcogen selected from the group consisting of sulfur and selenium and Y is a material located between layers of MX.sub.2. The compositions may be prepared by the steps of first forming a suspension of the MX.sub.2 in a body of water. A liquid which is immiscible with water is added to the suspension. The suspension and immiscible liquid are agitated together to form a temporary emulsion. The emulsion is allowed to rest until the water and the liquid separate with an interface therebetween. A sheet-like composition of MX.sub.2 :Y forms at the interface. Preferably, the MX.sub.2 is in exfoliated, singular molecular thickness layers suspended in the water.