As one environmentally benign technology for the removal of NO_x, the selective catalytic reduction of NO_x by hydrogen (H₂-SCR) in the presence of oxygen has attracted more and more attention. Recent progress in the H₂-SCR of NO_x has been reviewed with the focus on H₂-SCR catalysts and the reaction mechanisms. The effects of the reaction conditions (H₂, O₂, H₂O, CO and SO₂) on the performance of H₂-SCR catalysts have been discussed. Finally, the future research direction for the H₂-SCR of NO_x has been proposed.

中文翻译：

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NO选择性催化还原NO的研究进展X 由H2 在O的存在下2

作为一种用于去除NO _x的环境友好技术，在氧气存在下通过氢（H ₂ -SCR）选择性催化还原NO _x引起了越来越多的关注。回顾了NO _x的H ₂ -SCR的最新进展，重点是H ₂ -SCR催化剂和反应机理。讨论了反应条件（H ₂，O ₂，H ₂ O，CO和SO ₂）对H ₂ -SCR催化剂性能的影响。最后，NO _x的H ₂ -SCR的未来研究方向 已经提出。