Au promoted Pd/TiO₂ catalysts with different Pd loading were investigated for the selective catalytic reduction of NO_x by hydrogen (H₂-SCR). The results showed that 1%Pd-0.5%Au/TiO₂ catalyst exhibited the highest NO_x conversion and N₂ selectivity, as well as a wide activity temperature window. Moreover, the 1%Pd-0.5%Au/TiO₂ catalyst offered remarkable resistance to high gas hourly space velocity (GHSV). XRD, XPS and TEM results illustrated that the excellent H₂-SCR performance of 1%Pd-0.5%Au/TiO₂ catalyst was closely related to the formed PdAu alloy and the higher dispersion of active sites compared with 1%Pd/TiO₂. In-situ DRIFTS results revealed that more and new adsorbed nitrogen oxides species, as well as more adsorbed NH₃ and NH₄⁺ active species generated over 1%Pd-0.5%Au/TiO₂ catalyst, thus accelerating the ability to active H₂ atom and the subsequent reaction with adsorbed nitrogen oxides species.

研究了Au助催化的不同Pd负载量的Pd / TiO ₂催化剂对氢气（H ₂ -SCR）选择性催化还原NO _x的影响。结果表明，1％Pd-0.5％Au / TiO ₂催化剂表现出最高的NO _x转化率和N ₂选择性，以及宽的活性温度范围。此外，1％Pd-0.5％Au / TiO ₂催化剂对高气体时空速度（GHSV）具有显着的抵抗力。XRD，XPS和TEM结果表明1％Pd-0.5％Au / TiO ₂具有优异的H ₂ -SCR性能与1％Pd / TiO ₂相比，该催化剂与所形成的PdAu合金和较高的活性位分散密切相关。原位DRIFTS结果表明，超过1％Pd-0.5％Au / TiO ₂催化剂产生了更多和新的吸附氮氧化物，以及更多的吸附NH ₃和NH ₄ ⁺活性物质，从而提高了活性H ₂的能力。原子和随后与吸附的氮氧化物物质发生的反应。