Platinum group metal-free (PGM-free) catalyst with different loadings was investigated in air breathing electrodes microbial fuel cells (MFCs). Firstly, the electrocatalytic activity towards oxygen reduction reaction (ORR) of the catalyst was investigated by rotating ring disk electrode (RRDE) setup with different catalyst loadings. The results showed that higher loading led to an increased in the half wave potential and the limiting current and to a further decrease in the peroxide production. The electrons transferred also slightly increased with the catalyst loading up to the value of ≈3.75. This variation probably indicates that the catalyst investigated follow a 2x2e⁻ transfer mechanism. The catalyst was integrated within activated carbon pellet-like air-breathing cathode in eight different loadings varying between 0.1 mgcm⁻² and 10 mgcm⁻². Performance were enhanced gradually with the increase in catalyst content. Power densities varied between 90 ± 9 μWcm⁻² and 262 ± 4 μWcm⁻² with catalyst loading of 0.1 mgcm⁻² and 10 mgcm⁻² respectively. Cost assessments related to the catalyst performance are presented. An increase in catalyst utilization led to an increase in power generated with a substantial increase in the whole costs. Also a decrease in performance due to cathode/catalyst deterioration over time led to a further increase in the costs.

在空气呼吸电极微生物燃料电池（MFC）中研究了不同负载量的无铂族金属（无PGM）催化剂。首先，通过不同催化剂负载量的旋转环盘电极（RRDE）装置研究了催化剂对氧还原反应（ORR）的电催化活性。结果表明，较高的负载量导致半波电位和极限电流增加，并导致过氧化物产量进一步下降。随着催化剂负载量达到约 3.75，电子转移也略有增加。这种变化可能表明所研究的催化剂遵循 2x2e ^-转移机制。^{该催化剂以0.1 mgcm -2}至10 mgcm ^-2之间的八种不同负载量集成在活性炭颗粒状吸气阴极中。随着催化剂含量的增加，性能逐渐增强。功率密度在90±9μWcm ^-2和262±4μWcm ^-2之间变化，催化剂负载量分别为0.1mgcm ^-2和10mgcm ^-2。提出了与催化剂性能相关的成本评估。催化剂利用率的提高导致发电量增加，但整体成本大幅增加。此外，由于阴极/催化剂随着时间的推移而劣化导致性能下降，导致成本进一步增加。