Nanolayered Heterostructures of N-Doped TiO₂ and N-Doped Carbon for Hydrogen Evolution

Abstract

Both doping and compositing in TiO 2 are exceedingly effective strategies to overcome the compound's shortcomings, such as invalid visible-light response and enormous recombination of photogenerated carriers. Herein, a convenient and costeffective route has been put forward to in situ synthesize nanolayered heterostructure based on N-doped TiO 2 nanoparticles and Ndoped carbon (N-TiO 2 /NC) using 2D layered N-MXene (N−Ti 3 C 2 T x ) as the template. The as-obtained N-TiO 2 /NC nanocomposite displays greatly enhanced visible light absorption property, superior carrier separation and transport ability. As a result, the nanolayered N-TiO 2 /NC heterostructure exhibits a satisfactory H 2 evolution rate from water-splitting (102.6 μmol g −1 h −1 ) under visible-light without any additional cocatalyst. The study provides a new strategy for the synthesis of defective nanoheterostructure and expands the applications of MXene family.

A Robust Photocatalytic Hybrid Material Composed of Metal‐Organic Cages and TiO2 for Efficient Visible‐Light‐Driven Hydrogen Evolution

“…And the S 2p peaks position remained unchanged after MOC‐Q2 was loaded on the TiO 2 , indicating that there is no Ti−S bond formation between Ti atom and thiophene groups in the hybrid. For N 1s XPS spectrum of MOC‐Q2 (Figure S14B), the peak at 398.8 eV was assigned to the uncoordinated pyridine N atoms, which matched the results in the literature, [36] and the peaks at 399.6 and 400.8 eV were assigned to pyridine N−Pd and triphenylamine N−C 3 , respectively. Notably, the peaks at 398.8, 399.6 and 400.8 eV with a peak area ratio of 1 : 2 : 1 was observed in MOC‐Q2 and the area ratio was consistent with that of uncoordinated pyridine N, pyridine N−Pd, and triphenylamine N−C 3 included in MOC‐Q2.…”

Photocatalytic Hydrogen Evolution Coupled with Production of Highly Value‐Added Organic Chemicals by a Composite Photocatalyst CdIn2S4@MIL‐53‐SO3Ni1/2

“…[4,5] Because H 2 is an ideal intermediate in green energy cycle, photocatalytic synthesis of H 2 by splitting water is of significant importance. [6,7] However, the highly positive Gibbs free energy (ΔG θ = 237.1 kJ mol À 1 ) of the reaction would result in back-reaction that could heavily deteriorate the photocatalytic efficiency for overall water splitting. [8] Considering that the production of O 2 is insignificant, sacrificial agents (e. g. triethylamine, triethanolamine, ethanol and methanol) were usually used as electron donors to improve the H 2 evolution efficiency.…”

“…Attributed to the unique feature of harvesting free solar energy under green conditions, photocatalysis has been extensively studied in numerous fields, including water splitting, [1] carbon dioxide reduction, [2] molecular synthesis, [3] pollutant degradation and metal reduction [4,5] . Because H 2 is an ideal intermediate in green energy cycle, photocatalytic synthesis of H 2 by splitting water is of significant importance [6,7] . However, the highly positive Gibbs free energy (Δ G θ =237.1 kJ mol −1 ) of the reaction would result in back‐reaction that could heavily deteriorate the photocatalytic efficiency for overall water splitting [8] .…”

Hydrolytic Modification of SiO2 Microspheres with Na2SiO3 and the Performance of Supported Nano-TiO2 Composite Photocatalyst

“…However, TiO 2 also suffers from an easy combination of photogenerated electrons and holes [ 9 ], low utilization of sunlight [ 10 ], reduced photocatalytic effect due to particle agglomeration [ 11 ], and difficult recycling in wastewater [ 12 ]. Elemental doping [ 13 , 14 ], noble metal deposition [ 15 ], heterostructure construction [ 11 , 14 ], and morphology control [ 16 ] have been adopted to improve TiO 2 photocatalytic performance. It was found that loading TiO 2 onto carriers enhances photocatalytic performance and enables the recycling and reuse of TiO 2 , resulting in lower application costs [ 17 ].…”