In this paper, LiF and HCl were used to etch Ti3AlC2 to obtain MXene; Then, g-C3N4 and triazole were utilized to resp. modify MXene to obtain the hybrid g-C3N4/MXene (GM) and triazole/MXene (TM) composites.Morphologies, adsorption kinetics and thermodn., recycling and green plant cultivating, bactericidal properties, and the mechanism for absorption and bactericidal of MXene, GM, and TM were sufficiently presented.Compared to the MXene, the interlayer spacing of the TM and GM are exfoliated more perfectly with more active sites and excellent adsorption performance of the GM and TM composites for methylene blue (MB) from 47.48 mg/g to 866.86 mg/g and 340.26 mg/g.Importantly, with the incorporation of triazole, the adsorption performance and adsorption range of the TM are significantly improved, and more than 90 % MB removal could be achieved at pH of 2-10, which is much higher than that of most of the adsorbents reported in the previous studies.Moreover, according to DFT calculations of the GM and TM, it can be concluded that the binding energies of MXene, GM, and TM composites for MB are -9.53 Kcal/mol, -66.14 Kcal/mol and -55.51 Kcal/mol, resp.Furthermore, the bacteriostatic performance test shows that both GM and TM could enhance the bacteriostatic capacity of MXene, and the bacteriostatic performance of TM is more prominent owing to the effect of triazole.This work not only explores the modification method for the outstanding adsorption and bacteriostatic performance of hybrid MXene composites but also broadens the functional application scope of MXene-based composites, which provides novel ideas for the application of MXene-based composites in wastewater treatment.