TiO₂/Ti₃C₂ intercalated with g-C₃N₄ nanosheets as 3D/2D ternary heterojunctions photocatalyst for the enhanced photocatalytic reduction of nitrate with high N₂ selectivity in aqueous solution

Abstract

Recently, the nitrate as one of the water pollutant has caused widespread concerns. The nitrite and ammonium of the nitrate reduction products have been also regarded as contaminants. Thus, increasing...

In situ synthesis of N-doped TiO2 on Ti3C2 MXene with enhanced photocatalytic activity in the selective reduction of nitrate to N2

“…39 Moreover, the broad band ranging from 3300 to 3600 cm −1 was referred to as the stretching vibration of O–H terminations. 35 Similarly, the above signals were also detected in the spectra of both TM and NTM. Besides, the strong peak at ca.…”

“…21-1272), indicating that anatase TiO 2 was successfully fabricated on Ti 3 C 2 after calcination. 16,35 Compared with TM, the (101) peak of TiO 2 slightly shifted, indicating that nitrogen may be doped into TiO 2 of the TiO 2 /Ti 3 C 2 compound. 36 Moreover, the peaks located at 36.0° and 41.8° were assigned to Ti 3 C 2 , verifying the remaining Ti 3 C 2 in TiO 2 /Ti 3 C 2 composites after calcination.…”

Reaction mechanism and selectivity regulation of photocatalytic nitrate reduction for wastewater purification: progress and challenges

“…102,103 Unmodified TiO 2 exhibits negligible nitrate purification efficiency, and it is arduous to control the product distribution, which may release undesirable products in this progress that pollute the environment. The selectivity is expected to achieve by modification of TiO 2 including metal modification, 104 heterojunction construction, 105–107 and defect engineering. 102,108,109…”

“…For the TiO 2 /Ti 3 C 2 /g-C 3 N 4 (ref. 106) photocatalyst with 3D/2D ternary heterojunctions system, the holes left in the valence band of TiO 2 are captured by formic acid to generate CO 2 ˙ − , which promotes the generation of photogenerated electrons on the g-C 3 N 4 conduction band and highly selective reduction of nitrate to nitrogen. Similarly, formic acid used in TiO 2 and metal-modified TiO 2 systems also combines the characteristics of metals to promote the selectivity of reduction to nitrogen.…”

“…102,103 Unmodied TiO 2 exhibits negligible nitrate purication efficiency, and it is arduous to control the product distribution, which may release undesirable products in this progress that pollute the environment. The selectivity is expected to achieve by modication of TiO 2 including metal modication, 104 heterojunction construction, [105][106][107] and defect engineering. 102,108,109 Metal modication including mono-metal 110,111 and bimetals 15,112,113 had been proved to be an effective strategy to improve the efficiency and selectivity of nitrate reduction.…”