An example method of removing hydrogen sulfide from an input gas includes exposing an adsorbent material to an input gas to obtain an output gas. A concentration of hydrogen sulfide of the output gas is less than a concentration of hydrogen sulfide of the input gas. The adsorbent material includes copper oxide, magnesium oxide, and aluminum oxide. An atomic ratio of copper to magnesium to aluminum of the adsorbent material is X:Y:Z, where X is greater than or equal to 0.6 and less than or equal to 0.9, where Y is greater than or equal to 0 and less than or equal to 0.2, where Z is greater than or equal to 0 and less than or equal to 0.2, and where X+Y+Z is equal to 1.