National Laboratory of Solid State Microstructures, Collaborative Innovation, Center of Advanced Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, P. R. China.
Dalton Trans. 2018 Jul 10;47(27):8949-8955. doi: 10.1039/c8dt01219a.
Enhancing the charge separation by a semiconductor heterojunction is greatly promising and challenging for photoelectrochemical (PEC) water splitting. Here, we report for the first time the design and fabrication of a TaON/Ta3N5 heterojunction photoanode, in which the electrode Ta3N5 is the primary light absorber and TaON acts as an electron conductor. By combining the merits of the substantial light harvesting of Ta3N5 with the excellent charge transport capability of TaON, the TaON/Ta3N5 heterojunction photoanode, without any co-catalysts, shows a 350 mV negative shift of photocurrent onset potential to 0.65 V versus the reversible hydrogen electrode (RHE) compared to that of the Ta3N5 photoanode. The design and fabrication scheme can be readily extended to other (oxy)nitride semiconductors for heterojunction construction.
通过半导体异质结来增强电荷分离对于光电化学（PEC）水分解是非常有前景和具有挑战性的。在这里，我们首次报道了 TaON/Ta3N5 异质结光阳极的设计和制备，其中电极 Ta3N5 是主要的光吸收体，而 TaON 则作为电子导体。通过结合 Ta3N5 的大量光捕获和 TaON 的优异电荷传输能力的优点，在没有任何助催化剂的情况下，与 Ta3N5 光阳极相比，TaON/Ta3N5 异质结光阳极的光电流起始电位负移 350 mV，达到相对于可逆氢电极（RHE）的 0.65 V。该设计和制备方案可以很容易地扩展到其他（氧）氮化物半导体以进行异质结构建。
