LAUSR

At room temperature (RT), the weak and strong cluster‐centered luminescence of silver and copper iodide clusters, respectively, has been widely reported. Though the central metal ions show same d10 electrons and similar coordination mode, the mechanism of their distinct emission properties is still unclear, which restricts further applications. In this work, it is found that different photoluminescence quantum yields (PLQYs) are caused by various collision energy transfers between the metal ions in clusters, like a kind of aggregation‐caused quenching mechanism. Concretely, isostructural coordination polymers (CPs) of Ag(I) and Cu(I) iodide clusters are synthesized. The Ag(I)‐CP shows no luminescence at RT while the PLQY of Cu(I)‐CP boosts to 89%, in which short radius and weak collision between metal ions are found. Moreover, shorter Cu(I)‐Cu(I) and longer Ag(I)‐Ag(I) distances are realized in the similar structure and they display prospective luminescence, which proves the collisional quenching mechanism. Inspired of the above, the heterometallic materials with high sensitivities and wide sensing windows to temperature detection are obtained through tuning the metal content, and they are also fabricated into detecting sequences, which satisfies the wide‐range temperature sensing. This work proposes an efficient strategy to improve RT photoluminescence and broaden temperature sensing windows.