Preparation of polypyrrole/titanium nitride composite modified biochar and its application research in microbial fuel cells

In this study, the in situ growth method was employed to modify biochar with polypyrrole–titanium (PPy–TiN) nitride composites, aiming to enhance its performance as an anode material in microbial fuel cells (MFCs). A series of characterizations were conducted on the polypyrrole-modified corn straw biochar anode (PPy/CS), titanium nitride-modified corn straw biochar anode (TiN/CS), and polypyrrole/titanium nitride composite-modified biochar anode (PPy–TiN/CS) to evaluate the feasibility of the modification method and identify the optimal modification scheme. Characterization techniques included scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS), and Tafel analysis. SEM and FTIR analyses confirmed the successful integration of polypyrrole and titanium nitride with biochar, achieving a minimum solution resistance of 7.80 Ω and charge transfer resistance of 1.79 Ω. Compared to the unmodified electrode, the modified electrodes demonstrated improved performance, highlighting the need for the development of cost-effective, efficient, and durable anode materials.