Remarkable Acid Stability of Polypyrrole‐MoS4: A Highly Selective and Efficient Scavenger of Heavy Metals Over a Wide pH Range

The new material polypyrrole/MoS42−(MoS4‐Ppy), prepared by ion‐exchange of NO3‐ of NO3‐Ppy with MoS42−, displays high acid stability and excellent uptake for heavy metal ions such as Hg2+, Ag+, Cu2+, and Pb2+. The different maximum adsorption capacities (qm) for Cu2+, Pb2+, Hg2+, and Ag+ depend on the various binding modes arising from the different thiophilicity of these metal ions. The removals of Ag+ and Pb2+ reach >99.6% within 5 min, and for highly toxic Hg2+, >98% removal achieves at 1 min. At strong acid limit, the exceptional qm(Ag+) of 725 mg g−1 places the MoS4‐Ppy at the top of materials for such removal. Uptake kinetics of Ag+, Hg2+, and Pb2+ is extremely fast: >99.9% removal rates at wide pH range (0.5–6) within 1–5 min. Also, at strongly acidic conditions (pH ≈ 1), for highly toxic Hg2+, 100). MoS4‐Ppy is a superior and novel sorbent material for water remediation applications as well as precious metals recovery. The new material of polypyrrole/MoS42− (MoS4‐Ppy) displays high acid stability and excellent uptake for heavy metal ions of Hg2+, Ag+, Cu2+, and Pb2+. High distribution coefficients (≈107 mL g−1), rapid kinetics (99% uptake within 1–5 min), and exceptionally large maximum capacity (such as 725 mg g−1 for Ag+) especially at strong acidic condition place the MoS4‐Ppy at the top of materials.