Ever-growing energy demands, associated with the continuing increase in the world population, compel researchers to search for effective sustainable energy resources to maintain the synergy between global energy consumption and the sustainability of the world. Currently, with more than 65% of overall expended energy being lost as waste heat, it is of paramount financial and ecological advantage to capture this untapped waste heat and convert it into a reusable form. Thermoelectric (TE) materials, able to achieve an immediate and reversible change of heat into electricity, are believed to be a key contributor to future worldwide energy management.^1–4  However, the massive use of TE power generation in mass-market applications is restricted by the inaccessibility of cost-effective and high-performance TE materials.