摘要： AgCoO2 prepared by co-precipitation at low temperature (~ 80 °C) is characterized by physical and photo-electrochemical techniques. The X-ray diffraction shows broad peaks with a particle size of ~ 20 nm and a specific surface area of ～ 28 m2 g?1. The forbidden band (1.33 eV) is due to Ag+: d → d transition, further transition at 4.50 eV is assigned to the charge transfer. The transport properties, measured up to 650 K, indicate intrinsic conductivity: σ = σo exp{? 0.24 eV/kT (Ω-cm)?1}, supporting a phonon assisted conduction mechanism. An exchange current density of 1.27 mA cm?2 in Na2SO4 (0.1 M) solution is consistent with the electrochemical stability up to 0.8 VSCE. The capacitance measurement (C?2 - E) indicates p type conduction, with a flat band potential (Efb) of 0.26 VSCE and a holes density (NA) of 7.38 × 1019 cm?3 due to the oxygen insertion in the layered lattice. The electrochemical impedance spectroscopy (EIS) data, recorded in the range (1 mHz - Hz), reveals a predominant bulk contribution with a low depletion angle of 3° and a pseudo capacitive behavior. As application, AgCoO2 is tested for the hydrogen production upon visible illumination owing to the potential of its conduction band (?0.83 VSCE), less cathodic than that of H2O/H2 (~ ?0.5 VSCE). H2 evolution rate of 79 μmol g?1 min?1 is determined at neutral pH with a quantum yield of 1.92% in presence of NO2? as hole scavenger; no Ag deposition was observed after photocatalysis.