2D/2D Ti3C2 MXene/g-C3N4 nanosheets heterojunction for high efficient CO2 reduction photocatalyst: Dual effects of urea

Inside‐and‐Out Semiconductor Engineering for CO2 Photoreduction: From Recent Advances to New Trends

“…As each of the aforementioned steps needs to be well optimized to achieve highly active and selective photocatalysts, various structural design methods have been developed for promoting the photocatalytic CO 2 reduction performance, as briefly listed in the following: 1) Construction of nano‐/microstructures strategies can control the morphology, size, and shape of materials, which have substantial advantages for enhancing CO 2 photoreduction activity, such as shortening charge migration pathway, [ 126–128 ] increasing reactive catalytic sites, [ 129–133 ] boosting charge separation as well as extending optical transmission length. [ 134–138 ] 2) Doping and formation of solid solution are two main approaches to tailor the crystalline and band structures of photocatalysts.…”

Recent Advances in Functional 2D MXene‐Based Nanostructures for Next‐Generation Devices

“…Recent research studies have shown that MXenes have promising potential for photocatalytic applications, due to some distinct properties: i) the high carrier mobility in MXene-based system efficiently promoting the separation and migration of photogenerated electron-hole pairs; ii) the tunable band gap of MXenes by altering their surface chemistries, for example, the terminated -F, -O, or -OH groups, or the arrangements of surface groups; iii) the abundant surface groups with more active sites on the surface of MXene. [178][179][180] It is noted that Ti 3 C 2 T x has already been employed as an efficient co-catalyst in g-C 3 N 4 , [181][182][183][184] Bi 2 WO 6 , [185] BP, [178] AgInS 2 , [65,186] SrTiO 3 , [187] hematite, [154] , anatase, [179,188,189] and so on, to further enhance their photocatalytic performance. For example, in 2018, the 2D MXene Ti 3 C 2 T x /2D g-C 3 N 4 nanosheet heterostructures were rationally designed and successfully synthesized by calcination of bulk Ti 3 C 2 and urea, where urea not only acts as the gas template to process the exfoliation of Ti 3 C 2 into Ti 3 C 2 T x nanosheets, but also as the precursor of g-C 3 N 4 to obtain 2D MXene Ti 3 C 2 T x /2D g-C 3 N 4 nanosheet heterostructures.…”

“…The CO evolution as a function of 2D MXene Ti 3 C 2 T x /2D g-C 3 N 4 nanosheet heterostructures with different compositions, pure g-C 3 N 4 (UCN), and calcined product of mechanically mixed precursor 3D multi-layered Ti 3 C 2 particles and 2D g-C 3 N 4 nanosheets (M-10TC) can be seen in Figure 11a, where xTC represents the 2D MXene Ti 3 C 2 T x /2D g-C 3 N 4 nanosheet heterostructures with different amount (mg) of Ti 3 C 2 added into the reaction system. [181] Due to the metallic property of Ti 3 C 2 , there is no clear photoactivity observed for Ti 3 C 2 , [180,184] while UCN exhibits a weak photocatalytic performance, mainly ascribed to the fast recombination of change. [190,191] However, the photocatalytic performance of 2D MXene Ti 3 C 2 T x /2D g-C 3 N 4 nanosheet heterostructures exhibits modulated relationship with the Ti 3 C 2 amount, indicating that an excess of Ti 3 C 2 hinders the photoexcitation of UCN.…”

“…The hydrogen evolution reaction (HER) polarization curves of bare carbon paper (CP); Ti 3 C 2 T x ; N and S co-doped Reproduced with permission. [181] Copyright 2020, Elsevier B.V. e) Photocatalytic activity of TB0 to TB5; f) GC-MS spectra over TB2 after irradiation for several hours with different carbon sources; g) GC-MS analysis of reaction products with 12 C and 13 C as carbon sources, respectively; and h) energy level structure diagram of Bi 2 WO 6 and Ti 3 C 2 T x (1), and photo-induced electron transfer process at the interface of the heterostructures (2). Reproduced with permission.…”

“…Due to the excellent metal conductivity of MXenes efficiently promoting carrier transfer, they are widely utilized as co-catalysts, such as 2D Ti 3 C 2 T x /2D g-C 3 N 4 , [181,182,184] 2D Ti 2 CT x /2D g-C 3 N 4 , [190] and 2D Ti 3 C 2 T x /2D Bi 2 WO 6 heterostructures for enhanced performance. [185] Apart from that, it is also very vital for functional 2D MXenes to be applied into the degradation of organic matters due to the more serious environmental hazards.…”