熔融中间体运输导向合成富氨基g-C_(3)N_(4)纳米片用于高效光催化产H_(2)O_(2)

Molten Intermediate Transportation-Oriented Synthesis of Amino-Rich g-C_(3)N_(4) Nanosheets for Efficient Photocatalytic H_(2)O_(2) Production

为避免使用当前g-C_(3)N_(4)纳米片合成策略中的外加辅助,如模板、强酸、强碱等,本研究设计了一种g-C_(3)N_(4)熔融中间体运输的创新模式,在没有任何外加物质辅助情况下,成功一步合成富含氨基g-C_(3)N_(4)纳米片。该创新模式具体包括先将三聚氰胺放置在倒置坩埚的顶部平台上,随后进行一步煅烧。在煅烧过程中,三聚氰胺及其随后形成的g-C_(3)N_(4)中间体转变为熔融状态,并沿倒置坩埚外表面逐渐向下流动。这种熔融中间体运输模式可以有效减少其团聚,并使其依次分批聚合成富含氨基的g-C_(3)N_(4)纳米片。此外,所得富氨基g-C_(3)N_(4)纳米片的光催化产H_(2)O_(2)速率显著提高,约为85.8μmol·L^(-1)·h^(-1),是传统块体g-C_(3)N_(4)的2倍,这主要是因为除了其纳米片结构具有较大的比表面积外,富氨基结构可以有效增强对O_(2)原料和*OOH中间体的吸附,并加速*OOH高效转化为H_(2)O_(2)。该探究提供了一种创新模式来合成富含氨基的g-C_(3)N_(4)纳米片,并深入探究了其光催化机理。

To eliminate the additional assistance of previously reported strategies for the synthesis of g-C_(3)N_(4) nanosheets such as templates,strong acids and alkalis,in this study,an innovative pattern for transportation of molten g-C_(3)N_(4) intermediates,without any additional substance assistance,has been resoundingly established to produce amino-rich g-C_(3)N_(4) nanosheets.The innovative pattern concretely contains the preliminary placement of melamine onto the top platform of an inverted crucible and their subsequent one-step calcination.During the calcination process,melamine and its subsequently formed g-C_(3)N_(4) intermediate can transform into a molten state and gradually stream down along the outer surface of inverted crucible.This molten intermediate transportation pattern contributes to remarkably resist severe aggregation,resulting in the final polymerization into amino-rich g-C_(3)N_(4) nanosheets in sequence.Moreover,the resultant amino-rich g-C_(3)N_(4) nanosheets exhibit an evidently enhanced photocatalytic H_(2)O_(2)-production rate of ca.85.8μmol·L^(-1)·h^(-1),over 2 times superior to bulk g-C_(3)N_(4),mainly due to the fact that in addition to their nanosheet structures with enhanced specific surface areas,their amino-rich structures can efficiently reinforce the adsorption of O_(2) and*OOH intermediates to accelerate their effective transformation into H_(2)O_(2).This work delivers an innovative pattern to synthesize amino-rich g-C_(3)N_(4) nanosheets with an insight into the photocatalytic mechanism.