Three etchants are used to synthesize three different Ti3C2Tx (MXene) samples. The difference in chemical components, morphology and surface terminations of Ti3C2Tx and their influences on the conductivity, stability and flexibility are comprehensively analyzed. The underlying mechanism is investigated simultaneously. Besides, favorable annealing treatments and storage conditions are also proposed to optimize the properties of Ti3C2Tx. Display omitted •Three typical etchants HF, LiF/HCl, TMAOH are used to synthesize three different Ti3C2Tx (MXene) samples.•The difference in chemical components, morphology and surface terminations of Ti3C2Tx are comprehensively analyzed.•Favorable annealing treatments and storage conditions are also proposed to optimize the properties of Ti3C2Tx. Two-dimensional transition metal carbides or/and nitrides (MXenes) exhibit great development prospects in energy storage, catalysis, sensing and other fields due to their good properties. However, MXenes obtained from different etching conditions show great discrepancy on their electrical and mechanical properties, which will affect their applications to a certain degree. Unfortunately, few reports have systematically investigated such discrepancy and the underlying mechanism. Herein, three etchants and corresponding subsequent operations were used to synthesize three different Ti3C2Tx (MXene) samples. The difference in chemical components, morphology and surface terminations of Ti3C2Tx and their influences on the conductivity, stability and flexibility were comprehensively analyzed. The underlying mechanism has been investigated simultaneously. Based on this, favorable annealing treatments and storage conditions are also proposed to optimize the properties of Ti3C2Tx, which is believed of great meaning to the practical applications of Ti3C2Tx.