Peroxymonosulfate　(PMS)　Fenton-like　systems　have　emerged　as　promising　alternatives　to　hydrogen　peroxide　(H　2　O　2　).　Fenton　systems　are　currently　used　in　the　industry　owing　to　their　highly　efficient　utilization　rate　of　oxidizing　agents　and　wide　operating　pH　ranges.　Heterogeneous　Fenton-like　catalysts　are　promising　candidates　in　this　regard.　However,　self-aggregation　and　generation　of　ambiguous　reactive　oxygen　species　greatly　restrict　their　broad　application　in　practical　settings.　Herein,　a　redox　reaction　between　exfoliated　MXene　and　KMnO　4　facilitates　the　in-　situ　deposition　of　MnO　2　nanoparticles　on　the　surface　of　Ti-deficient　vacancies　of　MXene　(MXene/MnO　2　).　Owing　to　the　advantages　of　MXene　with　fast　charge　transfer　and　MnO　2　with　strong　PMS　activation　ability,　the　engineered　MXene/MnO　2　@PVDF　catalytic　membrane　exhibited　enhanced　activity　and　excellent　long-term　stability　for　various　refractory　organic　pollutants.　Experimental　observations,　combined　with　density　functional　theory　calculations,　revealed　that　the　exposed　Mn　sites　effectively　promoted　the　generation　of　1　O　2　.　Interestingly,　the　widespread　pathway　for　the　direct　generation　of　1　O　2　via　high-valent　Mn-oxo　phases　has　a　high　energy　barrier　(3.34　eV).　In　contrast,　the　pathway　that　uses　the　center　dot　OOH　species　as　intermediates　to　produce　1　O　2　is　energetically　more　viable　(1.84　eV).　This　work　offers　insights　into　the　in-　situ　engineering　of　transition　metal-oxides　on　MXene-based　membranes,　facilitating　their　implementation　in　remediating　micropollutant-contaminated　environmental　water.　(c)　2024,　Dalian　Institute　of　Chemical　Physics,　Chinese　Academy　of　Sciences.　Published　by　Elsevier　B.V.　All　rights　reserved.