聚电解质多层膜/α-Fe_2O_3改性阳极对MFC性能影响

The Effect of Modification of ITO Anode with Multi-layered Polyelectrolytes/α-Fe_2O_3 on the Performance of MFC

文章利用层层自组装技术将聚二甲基二烯丙基氯化铵(PDADMAC)、聚苯乙烯磺酸钠(PSS)及α-Fe_2O_3修饰到ITO导电玻璃上,并在其最外层修饰导电性良好的α-Fe_2O_3,将之作为微生物燃料电池(MFC)阳极与空白ITO进行比较。当外电阻为1 000Ω时,修饰了4层(PDADMAC/PSS)_4及1层α-Fe_2O_3的ITO阳极的MFC具有最高功率密度,为0.25 W/m^2。修饰了4层、8层(PDADMAC/PSS)_8及1层α-Fe_2O_3的ITO阳极的MFC最大电流均为0.45 mA,但修饰了4层的产电量更稳定。原子力显微镜数据表明(PDADMAC/PSS)_4/α-Fe_2O_3修饰的ITO导电玻璃的表面比较粗糙,这说明其具有较高的比表面积,更利于微生物的黏附。(PDADMAC/PSS)/α-Fe_2O_3修饰ITO后提高了MFC的产电量是由于ITO导电玻璃表面的物化性质改变促进了微生物产生的电子向阳极表面的传导所致。

Indium-tin oxide conductive glass(ITO) anode was modified by layer-by-layer assembled poly dimethyl diallyl ammonium chloride(PDADMAC)/poly(sodium-p-styrenesulfonate)(PSS) andα-Fe2 O3. The performance of microbial fuel cell(MFC) is dramatically increased by modification. Two kinds of polyelectrolyte multi-layers modified ITO were studied and compared with the blank ITO. When ITO/(PDADMAC/PSS)4/α-Fe2O3 was the anode, and the external resistance was 1 000Ω, the maximum power density was 0.25 W/m^2. The maximum current occurred, which was 0.45 mA, with two kinds of modified anode, and the current is more stable with ITO/(PDADMAC/PSS)4/α-Fe2 O3 anode. Atomic force microscope(AFM) image proved that ITO/(PDADMAC/PSS)4/α-Fe2 O3 surface was rougher than those of the blank ITO and ITO/(PDADMAC/PSS)8/α-Fe2 O3, which enable it to have a higher specific surface area for microbes to anchor and grow.ITO/(PDADMAC/PSS)4/α-Fe2 O3 and ITO/(PDADMAC/PSS)8/α-Fe2 O3 anode could improve MFC performance dramatically,which was attributed to the changes of physical and chemical properties of ITO and the improvement of electrons transfer ability from microbes to the anode.