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[Display omitted] • A CuO x catalyst supported on P-doped porous g-C 3 N 4 is synthesized easily. • P-doping increases the number of unpaired electrons in the catalyst. • Porous defects increase the catalyst surface area and active sites. • The unpaired electrons in the catalyst can directly inject into Cu active sites. • Catalyst performance and H 2 O 2 utilization efficiency are simultaneously improved. Copper oxides were supported on porous P-doped g-C 3 N 4 (Cu/p-PCN) by a stepwise calcination process. Elemental analysis, XPS, and ESR results show that P atoms enter the network of g-C 3 N 4 , and the thus-fabricated configuration could provide additional electrons for the conjugated system of g-C 3 N 4. As verified by TEM, XRD, XPS, and FTIR results, copper is mainly present as oxides on the catalyst surface and undergoes Cu-π interactions with porous P-doped g-C 3 N 4 (p-PCN). During the reaction, unpaired electrons in p-PCN can be injected into the Cu active sites, prompting the decomposition of H 2 O 2 into hydroxyl radicals (•OH). The degradation begins with the activation of H 2 O 2 into •OH radicals by the Cu(I) active center. The depleted Cu(I) centers are then regenerated by electron injection from P atoms rather than by the reaction between H 2 O 2 and Cu(I). Thus, the catalyst performance and H 2 O 2 utilization are greatly enhanced. Equally significantly, the porous structure of Cu/p-PCN also contributes appreciably to its performance by increasing the specific surface area and active sites. Cu/p-PCN exhibits better performance than many reported catalysts in similar conditions, robust resistance to interference from various ions, high degradation efficiency over a wide pH range, and excellent degradation ability for various pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-SSZ-13 catalysts with different Cu2+ species were synthesized successfully. • The balance between Cu2+-2Z and [Cu(OH)]+-Z exhibited optimal DeNOx performance. • The optimal ratio of Cu2+ species can promote the rapid formation of intermediates. In diesel vehicle exhaust after-treatment systems, high silica Cu-SSZ-13 has received increasing attention as a commercialized catalyst owing to its high efficiency in selective catalytic reduction reactions with NH 3 (NH 3 -SCR). However, research on the regulation of Cu2+ species within metal active centers in the pore structure of chabazite (CHA)-type zeolite to improve catalytic performance lacks sufficient depth. Herein, SSZ-13 zeolite with various Al distributions was prepared by adjusting the proportion of N,N,N-Trimethyl-1-adamantanaminiumhydroxide (TMAdaOH) and Na in the initial gel. Moreover, three representative Cu-SSZ-13 catalysts with different Cu2+ species were synthesized via an ion exchange method. 23Na MAS NMR and NO adsorption infrared spectroscopy results revealed that with increasing Na content and decreasing TMAdaOH concentration in the initial gel, the number of paired Al in the CHA framework gradually increased. Consequently, this increased the number of Cu2+-2Z sites near six-membered ring (MR) and reduced the amount of [Cu(OH)]+-Z sites near eight-MR. The fresh Cu-SSZ-13 catalyst, with a moderate amount of Cu2+-2Z and [Cu(OH)]+-Z, exhibited optimal catalytic performance across the entire temperature window. After hydrothermal aging, Cu-SSZ-13 with a higher concentration of Cu2+-2Z species featured optimal performance among all Cu-SSZ-13 catalysts above 400 °C. These findings indicated the significance of balancing the amount of both Cu2+-2Z and [Cu(OH)]+-Z in the Cu-SSZ-13 zeolite. Additionally, the results elucidated the reaction intermediates involved in the NH 3 -SCR process catalyzed by Cu-SSZ-13 with various Cu species. [ABSTRACT FROM AUTHOR]