Effect of charge compensation on the photoelectrochemical properties of Ho-doped SrTiO3 films

Zhao, Long; Fang, Liang; Dong, Wen; Zheng, Fengang; Shen, Mingrong; Wu, Tom
March 2013
Applied Physics Letters;3/25/2013, Vol. 102 Issue 12, p121905
Academic Journal
When Ho3+ ions are substituted at Sr2+ sites in SrTiO3 (STO), the excess positive charges are compensated via three complementary routes: (1) strontium vacancies, (2) titanium vacancies, and (3) conduction electrons. In this study, we show that the photoelectrochemical properties of Ho-doped STO films are dependent on the charge compensation mechanisms. The compensation mechanism via the titanium vacancies exhibits the highest photocurrent density, which is 1.7 times higher than that of the pure STO sample. Based on the measured dielectric properties and electrochemical impedance spectroscopy data, we propose that the enhanced dielectric constant of the films can enlarge the width of the space charge region at the film/liquid interface, which eventually leads to the increase of the photocurrent density. Further enhancement of photocurrent density is obtained in the samples decorated with appropriate amounts of Pt nanoparticles, showing the advantage of composites for achieving the efficient photoelectrochemical property.


Related Articles

  • Direct current voltage sweep and alternating current impedance analysis of SrZrO3 memory device in ON and OFF states. Lai, Chun-Hung; Liu, Chih-Yi // Applied Physics Letters;Dec2013, Vol. 103 Issue 26, p263505 

    The resistive switching (RS) effect of sputtered SrZrO3 memory cell is investigated by current-voltage (I-V) and impedance spectroscopy (IS) measurements for ON and OFF states. While the ON-state conduction in I-V exhibits ohmic relation of slightly temperature dependence, the OFF-state...

  • Detection of phenolic compounds using impedance spectroscopy measurements. Clarissa Olivati; Antonio Riul; Débora Balogh; Osvaldo Oliveira; Marystela Ferreira // Bioprocess & Biosystems Engineering;Jan2009, Vol. 32 Issue 1, p41 

    Abstract  Langmuir-Blodgett (LB) and layer-by-layer films (LbL) of a PPV (p-phenylenevinylene) derivative, an azo compound and tetrasulfonated phthalocyanines were successfully employed as transducers in an “electronic tongue” system for detecting trace levels of phenolic...

  • Charge disproportionation in TlGaSe2 crystals detected by dielectric spectroscopy. Seyidov, MirHasan Yu; Suleymanov, Rauf A.; Bakis, Yakub; Salehli, Ferid // Journal of Applied Physics;Oct2010, Vol. 108 Issue 7, p074114 

    The electrical properties of TlGaSe2 ferroelectric-semiconductor with layer crystalline structure in the direction parallel to the layers plane is studied by impedance spectroscopy in the frequency range 30 Hz-15 MHz. The impedance spectra were analyzed together with earlier results for...

  • Electron transport in electrospun TiO2 nanofiber dye-sensitized solar cells. Mukherjee, Kunal; Tai-Hou Teng; Jose, Rajan; Ramakrishna, Seeram // Applied Physics Letters;7/6/2009, Vol. 95 Issue 1, p012101 

    In this study dye-sensitized solar cells (DSCs) were fabricated using electrospun TiO2 nanofibers. Electrochemical impedance spectroscopy and open-circuit voltage decay were used to analyze electron transport in electrospun nanofibers and determine their applicability in DSCs. The...

  • Effects of dye adsorption on the electron transport properties in ZnO-nanowire dye-sensitized solar cells. Wu, Jih-Jen; Chen, Guan-Ren; Yang, Hung-Hsien; Ku, Chen-Hao; Lai, Jr-Yuan // Applied Physics Letters;5/21/2007, Vol. 90 Issue 21, p213109 

    Mercurochrome and N3 dyes are employed to be the sensitizers in the ZnO-nanowire (NW) dye-sensitized solar cells (DSSCs). A lower fill factor is obtained in the N3-sensitized cell which results in comparable efficiencies in both ZnO-NW DSSCs although the N3 molecules possess a wider absorptive...

  • Bipolar carrier transport in tris(8-hydroxy-quinolinato) aluminum observed by impedance spectroscopy measurements. Ishihara, Shingo; Hase, Hiroyuki; Okachi, Takayuki; Naito, Hiroyoshi // Journal of Applied Physics;Aug2011, Vol. 110 Issue 3, p036104 

    We studied bipolar carrier transport in tris(8-hydroxy-quinolinato) aluminum (Alq3) thin films using impedance spectroscopy (IS). Two transit times were observed in the impedance spectra of the Alq3 double-injection diodes. The mobilities determined from the transit times are in good agreement...

  • Two dielectric relaxation mechanisms observed in lanthanum doped barium strontium titanate glass ceramics. Zhang, Yong; Ma, Tao; Wang, Xiangrong; Yuan, Zongbao; Zhang, Qian // Journal of Applied Physics;Apr2011, Vol. 109 Issue 8, p084115 

    The dielectric relaxation at temperatures ranging from 100 °C to 550 °C in lanthanum-doped barium strontium titanate glass ceramics has been investigated by measurements of both dielectric temperature curve and complex impedance spectroscopy. The temperature dependence of dielectric...

  • Comparison Study of Volatile Corrosion Inhibitors in Steam And Cl Gas Environment on Mild Steel. Lavanya, K.; Kannan, P.; Palanisamy, K.; Natesan, M. // Arabian Journal for Science & Engineering (Springer Science & Bu;Jul2014, Vol. 39 Issue 7, p5381 

    The objective of the study was to synthesize and characterize the four different organic amides, such as octylpalmamide (OTP), octylstearamide (OTS), octylcaprilamide (OTC) and dicyclohexylaminebenzotriazole (DCHA.BTZ) and also characterize its corrosion protection behavior using them as...

  • Electrical Conductivity of Composite Materials Based on Fine-Particle Silicon near the Metal�Insulator Transition. Poklonskii, N. A.; Gorbachuk, N. I.; Pototskii, I. V.; Trofimchuk, D. A. // Inorganic Materials;Nov2004, Vol. 40 Issue 11, p1133 

    Si/SiO2 composites containing 17, 19, and 21 wt % crystalline B-doped Si particles (near the insulator-metal transition) are studied by impedance spectroscopy. The results indicate that, at low frequencies, the nonlinear variation of the real part of electrical conductivity, Re?, with applied dc...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics