Colloidal semiconductor nanocrystals (NCs), especially cadmium (Cd)- and lead (Pb)-containing ones, have been proved to be the promising materials for photoelectronic energy conversion applications. However, the high toxicity and cost of these materials restrict their widespread use. Zinc (Zn)-containing colloidal semiconductor NCs are non-/less toxic and environmentally friendly materials, manifesting in stimulating optical and electronic properties with relevance to a broad scope of applications including light-emitting diodes (LEDs), sensors, photocatalysts, and more. In this Review, we elaborate on the shape control of Zn-containing colloidal semiconductor NCs achieved by a variety of wet-chemical synthetic approaches. Moreover, the formation of core-shell, doped, and hybrid structures based on Zn-containing colloidal semiconductor NCs allow for the optimization of their functionalities, which underpin stimulating photoelectronic energy conversion applications in quantum-dot LEDs (QLEDs), photodetectors, and photocatalysis. Zn-containing colloidal semiconductor NCs that combine the green chemistry with sustainable developments possess a bright future.