The dataset contains 2D reconstructions of the Ag catalyst obtained using $in$ $situ$ ptychography. The Ag catalyst specimens were mounted on MEMS-based and TEM chips and studied under reaction conditions. The ptychography was performed at the P06 beamline of PETRA III in DESY, Hamburg, Germany. The specimens were treated in air or inert (He) conditions and heated up to 650 $^{\circ}$C under atmospheric pressures. A detailed description of the dataset can be found in the corresponding readme file and its associated manuscript publication.