Free chlorine (FC) species are important oxidants for organic synthesis and environmental remediation. However, due to competitive water oxidation, it’s hard to obtain satisfied photoelectrochemical Faradic efficiency (FE) of FC via energetically unfavorable •Cl intermediate. Herein, we developed a non-radical strategy to realize efficient and stable FC production. High FE (86.2 %), high partial photocurrent density (2.8 mA/cm2) and excellent stability were achieved even under the conditions of diluted Cl (0.1 M) and neutral pH. Furthermore, compared with BVO, BVO@AgCl exhibited multi-fold faster rates for chlorine-mediated oxidations of styrene and arsenite with superior FEs (90.0 % vs. 59.4 %; 89.3 % vs. 47.3 %). Mechanistically, photogenerated holes are accumulated at AgCl sites (Cl+). FC is catalytically produced from the nucleophilic attack of Cl to Cl+, which bypasses •Cl intermediate and energetically outcompetes water oxidation. This work provides promising photoelectrochemical systems for highly efficient and stable production of FC, promoting high-value-added chemical synthesis and water treatment.