Regulating directional transfer of electrons on polymeric g-C3N5 for highly efficient photocatalytic H2O2 production
Regulating directional transfer of electrons on polymeric g-C3N5 for highly efficient photocatalytic H2O2 production
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DOI：
10.1016/j.jcis.2022.07.080
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发表时间：
2022-07-22
影响因子：
9.9
通讯作者：
Ao, Yanhui
中科院分区：
文献类型：
--
作者：
Che, Huinan;Wang, Jian;Ao, Yanhui
石墨碳氮化物（g-C3 N5）由于其比g-C3 N4更高的热力学稳定性和更好的电子性质而被广泛应用于各种光催化反应中。然而，赋予g-C（3）N（5）光催化过氧化氢（H2 O2）生产的高性能仍然具有挑战性。在此，钾和碘共掺杂到g-C3 N5（g-C3 N5-K，I）中，用于高效地光催化产生H2 O2。结果表明，g-C_3 N_5-K，I（2933.4 μ M·h ~（-1））的光催化H_2 O_2生成速率是g-C_3 N_5的84.22倍。K和I的共掺杂显著提高了催化剂的氧（O-2）吸附能力、双电子氧还原反应的选择性（2 e（-）ORR）和载流子分离效率，是其光催化产H2 O2活性提高的主要原因。密度泛函理论（DFT）计算表明，O-2分子更有利于吸附在g-C3 N5-K，I上。激发态的结果进一步表明，光生电子可以被定向驱动到吸附的O-2分子上，有效地活化O-2分子生成H2 O2.这一发现将有助于设计和合成g-C3 N5基光催化剂用于H（2）O（2）生产的新见解。(C)2022爱思唯尔公司All rights reserved.
Graphite carbon nitride (g-C3N5) has been widely used in various photocatalytic reactions due to its higher thermodynamic stability and better electronic properties compared to g-C3N4. However, it is still challenging to endow g-C(3)N(5 )with high performance on photocatalytic hydrogen peroxide (H2O2) production. Herein, potassium and iodine are co-doped into g-C3N5 (g-C3N5-K, I) for photocatalytic production of H2O2 with high efficiency. As expected, the photocatalytic H(2)O(2 )production rate over the g-C3N5-K, I (2933.4 mu M h(-1)) reaches to 84.22 times as that of g-C3N5. The excellent photocatalytic H2O2 production activity is mainly ascribed to the co-doping of K and I, which significantly improves the capacity of oxygen (O-2) adsorption, selectivity of two-electrons oxygen reduction reaction (2e(- )ORR) and separation efficiency of charge carriers. The density functional theory (DFT) calculations reveal that O-2 molecules are more conducive to being adsorbed on g-C3N5-K, I. Besides, the result of excited states further indicates that photo-generated electrons can be directionally driven to the adsorbed O-2 molecules, which are effectively activated to form H2O2. The findings will contribute to new insights in designing and synthesizing g-C3N5 based photocatalysts for the H(2)O(2 )production. (C) 2022 Elsevier Inc. All rights reserved.