The　development　of　efficient　photocatalyst　is　critical　for　the　practical　application　of　photocatalysis.　Herein,　Ti3C2　MXenes,　a　kind　of　2D-layered　material,　is　successfully　coupled　with　g-C3N4　sheets　under　ultrasound　irradiation.　A　series　of　characterization　methods　are　adopted　for　the　investigation　of　the　obtained　samples.　The　consequences　reflect　that　for　the　successful　formation　of　2D/2D　schottky　junction　and　a　new　Ti-N　bond　between　g-C3N4　and　Ti3C2.　Moreover,　photocatalytic　measurements　demonstrate　Ti3C2　MXenes　is　an　efficient　activator　for　g-C3N4　to　promote　its　photocatalytic　reactivity.　The　photocatalytic　fixation　of　N-2　tests　manifest　that　the　optimized　sample　of　TC-CN-1　(g-C3N4　with　the　1　wt%　Ti3C2　MXene　loading)　shows　the　highest　generation　yield　of　NH4+　(601　umol　L-1.gcat(-1).h(-1)),　which　is　3.64-fold　higher　than　that　of　pristine　g-C3N4　(203　umol　L-1.gcat(-1).h(-1)).　Furthermore,　the　Ti3C2/g-C3N4　show　superior　photocatalytic　conversion　of　CO2　to　CO　or　CH4　yields　than　that　of　g-C3N4.　Besides,　the　photocatalytic　degradation　measurements　show　that　only　33.6%　of　levofloxacin　can　be　decomposed　by　pristine　g-C3N4,　while　the　removal　ratio　of　levofloxacin　reaches　72%　for　g-C3N4　with　1　wt%　loading　of　Ti3C2　MXene　under　visible　light　illumination　for　30　min.　The　photocatalytic　improvements　are　confirmed　to　benefit　from　the　faster　separation　of　photogenerated　electrons　and　holes,　higher　light　response　ability,　and　more　active　sites.　This　study　demonstrates　that　Ti3C2/g-C3N4　schottky　junction　is　a　promising　photocatalyst　for　the　photocatalytic　nitrogen　fixation,　and　antibiotics　degradation.　(C)　2021　Elsevier　B.V.　All　rights　reserved.