In this study, the degradation efficiency and electricity generation of the azo dyes affected by the functional groups and molecular structure in a solar photocatalytic fuel cell (PFC) system were investigated and discussed in detail. Four different azo dyes such as, Acid Orange 7 (AO7), Acid Red 18 (AR18), Reactive Black 5 (RB5), Reactive Red 120 (RR120) with different molecular structure were evaluated. The degradation efficiency of AO7, AR18, RB5 and RR120 achieved 5.6 ± 0.3%, 11.1 ± 0.6%, 41.9 ± 0.9% and 52.1 ± 1.3%, respectively, after 6 h irradiated under solar light. In addition, the maximum power density, P_max for AO7, AR18, RB5 and RR120 was 0.0269 ± 0.01, 0.111 ± 0.03, 1.665 ± 0.67 and 4.806 ± 1.79 mW cm⁻², respectively. Meanwhile, the concentration of COD for AO7, AR18, RB5 and RR120 reduced to 16 ± 0.1, 10 ± 0.3, 7 ± 0.6 and 3 ± 0.9 mg L⁻¹, respectively. The concentration ratio of benzene / naphthalene, benzene / azo bond and naphthalene / azo bond, respectively, was analyzed to investigate the impact of the functional groups over photodegradation of the azo dyes in PFC. Electron releasing groups (-OH and –NH₂) and electron withdrawing groups (-SO₃Na) which attached to the naphthalene or benzene ring also played a pivotal role in the degradation mechanism.

在这项研究中，对偶氮染料在太阳能光催化燃料电池（PFC）系统中受官能团和分子结构影响的降解效率和发电进行了详细研究。评价了四种不同的偶氮染料，例如具有不同分子结构的酸性橙7（AO7），酸性红18（AR18），活性黑5（RB5），活性红120（RR120）。在太阳光下照射6 h，AO7，AR18，RB5和RR120的降解效率分别达到5.6±0.3％，11.1±0.6％，41.9±0.9％和52.1±1.3％。此外，AO7，AR18，RB5和RR120的最大功率密度P _max为0.0269±0.01、0.111±0.03、1.665±0.67和4.806±1.79 mW cm ^-2， 分别。同时，AO7，AR18，RB5和RR120的COD浓度分别降至16±0.1、10±0.3、7±0.6和3±0.9 mg L ^-1。分析了苯/萘，苯/偶氮键和萘/偶氮键的浓度比，以研究官能团对PFC中偶氮染料光降解的影响。连接到萘或苯环上的电子释放基团（-OH和-NH ₂）和吸电子基团（-SO ₃ Na）在降解机理中也起着关键作用。