题目：

Ageing mechanisms of highly active and stable nickel-coated silicon photoanodes for water splitting

作者：

Tingting Han^1,a, Yuanyuan Shi^1,a, Xiaoxue Song¹, Antonio Mio², Luca Valenti², Fei Hui¹, Stefania Privitera², Salvatore Lombardo², Mario Lanza^1,*

单位：

¹Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren-AiRoad, Suzhou 215123, China. 

²Institute for Microelectronics and Microsystems, National Research Council (IMMCNR),533 Stradale Primosole, 95121 Catania, Italy.

^a These authors contributed to this work equally

摘要：

The photoelectrochemical (PEC) water splitting cell, a device that uses sunlight to produce hydrogen, hasgarnered very much interest due to its simple structure, low fabrication cost and good performance. Inthese cells, a semiconductor photoelectrode is immersed in a liquid and, when illuminated, hydrogenand/or oxygen can be generated on its surface by electrolysis. Metal catalysts are often used to enhancethe activity of the semiconductor, but the lifetime of the semiconductor photoelectrode is still the mainbottleneck of this technology. In this manuscript we report the ageing mechanisms of siliconphotoanodes coated with nickel films of different thicknesses (under the light-driven oxygen evolutionreaction, OER). The n-Si photoanodes coated with 2 nm-thick, 5 nm-thick and 10 nm-thick nickel layersshowed lifetimes of _18 h, _150 h and >260 h, respectively. While the 2 nm-thick sample degraded dueto the formation of a thin SiO_X layer at the metal�silicon interface, the performance of the thickersamples decreased due to the formation of holes. The 5 nm-thick and 10 nm-thick nickel films turned

into homogeneous potassium-free NiO_X films suitable for water splitting, and this conversion markedlyenhanced the performance of the cells. The density/size of holes in the surface decreased/increasedwith the metal thickness. The potassium contamination in the 2 nm-thick Ni sample took place in theform of nanofilaments, and we demonstrated that the widely used X-ray photoelectron spectroscopytests are blind to these features, which may have been ignored in all previous reports. These resultscould be useful for understanding the degradation and enhancing the yield of water-splitting solar cells.

影响因子：

8.262

分区情况：

一区

链接：

http://pubs.rsc.org/en/content/articlehtml/2016/ta/c5ta09990k

责任编辑：向丹婷 联系方式：dtxiang@suda.edu.cn