Manganese oxide (MnOx) was an effective sorbent for capturing elemental mercury (Hg-0) from coal-fired flue gas, but its usage was markedly limited by its lower porosity, lower temperature range, and sensitivity to sulfur dioxide (SO2). Tin (Sn) and iron (Fe) were tested for their ability to enhance MnOx sorbent, and the Fe-Sn-MnOx complex exhibited excellent performance as a novel mercury sorbent. SnO2 appeared to be inert for Hg-0 adsorption, but it could act as a suitable support to disperse MnOx, which helps to produce more activated sites. The BET surface areas increased by approximately 10 times, and there was an increase of 3 times the Hg-0 adsorption capacity. The available temperature range of the sorbent can be extended from 100 to 300 degrees C. Specifically, the presence of Fe can significantly improve the SO2 resistance of the sorbent. Furthermore, the mechanism of adsorption and SO2 tolerance at high temperatures was investigated by in situ Diffuse Reflectance Infrared Fourier Transform spectra (DRIFTs); Fe reacted with SO2 when O-2 was present, which could protect manganese active sites from being poisoned by SO2. (C) 2014 Elsevier Ltd. All rights reserved.