Silicon Carbide Derived from Chicken Manure for Highly Efficient Photocatalytic and Electrocatalytic Sensing Properties

Silicon carbide (SiC) with a rhombohedral structure and irregular microscale particles was prepared using chicken manure and silica sol and characterized by various techniques. The optimal preparation parameters for SiC from chicken manure (CM-SiC) are determined by controlling the reaction temperature, time, and In content. The CM-SiC acts as a highly efficient visible-light photocatalyst for removing rhodamine B (RhB) and methylene blue (MB) with good photocatalytic stability. For the RhB and MB removal using 30 mg of CM-SiC, 20 mL of RhB and MB solution (10 mg·L–1) can be removed under solar light for 150 and 180 min, respectively. The CM-SiC can also be used as the electrocatalyst for simultaneously detecting Hg2+, Pb2+, and Cd2+ by the square wave voltammetry method. Three stripping peaks exist at −0.75 V, −0.55 V, and +0.69 V for Hg2+, Pb2+, and Cd2+, respectively. Operating parameters for detecting Hg2+, Pb2+, and Cd2+ simultaneously were optimized. The limit of detection (LOD) and linear range are 1.18 nM and 0.01–1000 μM (Hg2+), 0.79 nM and 0.001–100 μM (Pb2+), and 3.26 nM and 0.01–1000 μM (Cd2+), respectively. The CM-SiC-modified electrode shows good selectivity, reproducibility, stability, and applicability, making it a promising electrode material for simultaneous detection of Hg2+, Pb2+, and Cd2+.