Interface induce growth of intermediate layer for bandgap engineering insights into photoelectrochemical water splitting.

Jian Zhang,Qiaoxia Zhang,Xing’Ao Li,Lianhui Wang,Wei Huang

doi:10.1038/srep27241

Abstract

A model of interface induction for interlayer growing is proposed for bandgap engineering insights into photocatalysis. In the interface of CdS/ZnS core/shell nanorods, a lamellar solid solution intermediate with uniform thickness and high crystallinity was formed under interface induction process. Merged the novel charge carrier transfer layer, the photocurrent of the core/shell/shell nanorod (css-NR) array was significantly improved to 14.0 mA cm−2 at 0.0 V vs. SCE, nearly 8 times higher than that of the perfect CdS counterpart and incident photon to electron conversion efficiency (IPCE) values above 50% under AM 1.5G irradiation. In addition, this array photoelectrode showed excellent photocatalytic stability over 6000 s. These results suggest that the CdS/Zn1−xCdxS/ZnS css-NR array photoelectrode provides a scalable charge carrier transfer channel, as well as durability, and therefore is promising to be a large-area nanostructured CdS-based photoanodes in photoelectrochemical (PEC) water splitting system.

Highlights

We synthesized a dense array of CdS/ZnS core/shell nanorods film through a simple two-step aerosol assisted chemical vapor deposition (AACVD) method[23]
Original CdS nanorod and CdS/Zn1−xCdxS/ZnS core/shell/shell nanorod (css-NR) photoanodes were further tested under chopped illumination of sunlight (100 mW cm−2) with an applied potential of −0.5 V vs. saturated calomel electrode (SCE)
From a practical application standpoint, the stabilities of CdS array and CdS/Zn1−xCdxS/ZnS css-NR photoanodes were tested for prolonged period of 6000 s fixed potential of −0.5 V vs. SCE under AM 1.5G simulated

Summary

Introduction

The lattice well matched lamellar SrTiO3 (4-nm-thick) growing on the surface of silicon by molecular beam epitaxy can act as a protection layer, as well as a tunneling junction for charge transportation due to the low density of interface defects[22]. We used a simple AACVD method to induce the growth of ultrathin layers of Zn1−xCdxS (~12 nm) on the interface of CdS/ZnS core/shell nanorods. The intermediate layer Zn1−xCdxS with lattice well matched can act as a bridge to smooth the band gap between CdS and ZnS for the establishment of two low density of defect states of the interfaces in the unique one-dimensional core/shell arrays[22]. The growth of ultrathin intermediate layer by interface induction will advance the utilization of different core/shell nanomaterials in the PEC water splitting applications

Methods

Results

Conclusion