Fig. 2: Representative TEM image and the catalytic performances of the PdSn nanowire catalysts in the direct H₂O₂ synthesis (DHS).

a Representative TEM image of the unsupported PdSn nanowire catalyst prepared by two-step (unsupported Pd_L/PdSn-NW). b H₂O₂ producibility of the supported Pd_L/PdSn-NW and Sn_x/PdSn-NW catalysts with different Pd/Sn ratios after annealing in air (350 °C, 8 min), demonstrating the addition of Sn has negative effect on the producibility of H₂O₂. c H₂O₂ producibility, hydrogenation, and decomposition of the supported Pd_L/PdSn-NW catalyst annealing at different temperatures in air, showing that the supported Pd_L/PdSn-NW annealing at 400 °C did not catalyze the hydrogenation and decomposition. d The comparison of the H₂O₂ producibility, hydrogenation, and decomposition of supported Pd_L/PdSn-NW catalyst with other Pd catalysts (Table 1). The error bars in b–d show the standard deviation in the measurements. The standard deviation was achieved from the repeated runs of three to five times using fresh catalyst each time. The error bars refers to the standard deviation of multiple times measurements of hydrogen peroxide productivity.