A composite photocatalyst, sliver/graphitic carbon nitride/pre-treated carbon fiber paper (Ag/g-C3N4/t-CFP), has been innovatively designed and successfully fabricated by loading Ag and g-C3N4 species on t-CFP using the combined methods of thermal polymerization and improved electroless plating (IEP) through ultrasonic spray atomization (USA). A micro-droplet system, USA is able to eliminate the adverse influence of concentration gradient effectively. The samples obtained were carefully characterized in terms of morphology, phase, chemical structure, and optical performance. Results suggested that compared with the conventional electroless plating (CEP), IEP strategy could ensure a better dispersibility and smaller size of Ag nanoparticles. Accordingly, the IEP-prepared Ag/g-C3N4 photocatalyst on t-CFP (ACNT-iep) exhibited a pseudo-first-order kinetics constant 12 times higher than that of the neat g-C3N4 on t-CFP for methylene blue (MB) degradation. Photoluminescence (PL) and electrochemical impedance spectra (EIS) demonstrated a more efficient separation of photogenerated carriers in ACNT-iep at the same time. The photocatalytic activity of ACNT-iep could be maintained at a high level over five cycles. (C) 2018 Elsevier Inc. All rights reserved.