Electronic Structure Engineering of Cu2O Film/ZnO Nanorods Array All-Oxide p-n Heterostructure for Enhanced Photoelectrochemical Property and Self-powered Biosensing Application

Abstract

We have engineered the electronic structure at the interface between Cu2O and ZnO nanorods (NRs) array, through adjusting the carrier concentration of Cu2O. The electrodeposition of Cu2O at pH 11 acquired the highest carrier concentration, resulting in the largest interfacial electric field between Cu2O and ZnO, which finally led to the highest separation efficiency of photogenerated charge carriers. The optimized Cu2O/ZnO NRs array p-n heterostructures exhibited enhanced PEC performance, such as elevated photocurrent and photoconversion efficiency, as well as excellent sensing performance for the sensitive detection of glutathione (GSH) in PBS buffer even at applied bias of 0 V which made the device self-powered. Besides, the favorable selectivity, high reproducibility and extremely wide detection range, make such heterostructure a promising candidate for PEC biosensing applications, probably for the extended field of PEC water splitting or other solar photovoltaic beacons.

A photoelectrochemical biosensor for determination of DNA based on flower rod-like zinc oxide heterostructures

“…The increased absorptive profile occurs over wavelengths less than 430 nm, which reaches an absorbance plateau at 360 nm (curve a). A little absorbance can be observed between 450 nm -600 nm, which may have resulted from the scattering effect of nanoparticles array structure [30]. Because DNA does not absorb visible light [2], there is no obvious enhancement in the visible wavelength range.…”

“…Then, the substrates were seeded by spin coating (1000 rpm, 39 s) with 5 mM Zn(Ac) 2 ·2H 2 O in ethanol, followed by thermal decomposition at 300°C for 20 min. The seeded substrates were placed into the growth solution consisted of 30 …”

Cuprous Oxide as a Potential Low‐Cost Hole‐Transport Material for Stable Perovskite Solar Cells

“…Cuprous oxide (Cu 2 O), with ab and gap of 2.2-2.8 eV,i sapromising and environmentalfriendly p-type HTM for p-n junction solar cells. [15] Moreover, very large hole mobility (100 cm 2 V À1 s…”

Design of sandwich-structured ZnO/ZnS/Au photoanode for enhanced efficiency of photoelectrochemical water splitting

“…the light absorption and carrier transport of the photoelectrode largely determines the capability of the PEC cell for water splitting. Lightweight active semiconductors or metal oxides such as titanium dioxide (TiO 2 ), zinc oxide (ZnO), hematite (Fe 2 O 3 ), and cuprous oxide (Cu 2 O) have shown great potential as photoelectrodes for hydrogen generation [4][5][6][7][8][9][10][11][12][13]. As a common and inexpensive semiconductor, ZnO has been extensively explored in a nanosized form for solar energy conversion, because of its excellent electron mobility, electron-transfer efficiency (115-155 cm 2 /(V·s)) [14], abundant potential morphologies, and good environmental compatibility [15][16][17][18].…”