Terminology, Relative Photonic Efficiencies and Quantum Yields in Heterogeneous Photocatalysis. Part II: Experimental Determination of Quantum YieldsA draft version of this paper was published previously in part in [J. Photochem. Photobiol. A:Chem., J. Adv. Oxid. Technol.; IAPS Newsletter and EPA Newsletter] to solicit comments and critiques from the scientific and engineering community. Moreover, during the preparation the draft proposal was submitted to a number of distinguished photochemists and photocatalycists to get their views.

2016 ◽  
Author(s):  
Angela Salinaro ◽  
Alexei V. Emeline ◽  
Jincai Zhao ◽  
Hisao Hidaka ◽  
Vladimir K. Ryabchuk ◽  
...  
Keyword(s):  
Experimental Determination ◽  
Heterogeneous Photocatalysis ◽  
Quantum Yields ◽  
Engineering Community ◽  
Draft Proposal ◽  
Draft Version

scholarly journals Photocatalytic Activity: Experimental Features to Report in Heterogeneous Photocatalysis

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1990 ◽  
Author(s):  
Md. Hoque ◽  
Marcelo Guzman
Keyword(s):  
Reaction Rate ◽  
Monochromatic Light ◽  
Heterogeneous Photocatalysis ◽  
Research Articles ◽  
Quantum Yields ◽  
Characterization Methods ◽  
Valuable Data ◽  
Photocatalytic Activities ◽  
Scientific Papers

Heterogeneous photocatalysis is a prominent area of research with major applications in solar energy conversion, air pollution mitigation, and removal of contaminants from water. A large number of scientific papers related to the photocatalysis field and its environmental applications are published in different journals specializing in materials and nanomaterials. However, many problems exist in the conception of papers by authors unfamiliar with standard characterization methods of photocatalysts as well as with the procedures needed to determine photocatalytic activities based on the determination of “apparent quantum efficiencies” within a wavelength interval or “apparent quantum yields” in the case of using monochromatic light. In this regard, an astonishing number of recent research articles include claims of highly efficient (photo)catalysts or similar terms about materials with superior or enhanced efficiency for a given reaction without proper experimental support. Consequently, the comparison of the efficiencies of photocatalysts may result as being meaningless, especially when reports are only based on expressions determining (1) a reaction rate per weight of catalyst or its surface area, (2) quantum efficiencies or quantum yields, and (3) turnover frequencies or turnover numbers. Herein, we summarize the standards needed for reporting valuable data in photocatalysis and highlight some common discrepancies found in the literature. This work should inform researchers interested in reporting photocatalysis projects about the correct procedures for collecting experimental data and properly characterizing the materials by providing examples and key supporting literature.

Terminology, relative photonic efficiencies and quantum yields in heterogeneous photocatalysis. Part II: Experimental determination of quantum yields

1999 ◽  
Vol 71 (2) ◽  
pp. 321-335 ◽  
Author(s):  
Angela Salinaro ◽  
Alexei V. Emeline ◽  
Jincai Zhao ◽  
Hisao Hidaka ◽  
Vladimir K. Ryabchuk ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Visible Region ◽  
Heterogeneous Photocatalysis ◽  
Quantum Yields ◽  
Yield Data ◽  
Normal Absorption ◽  
The One ◽  
Solid Liquid ◽  
Photonic Efficiency

In the preceding article [Serpone and Salinaro, Pure Appl. Chem., 71(2), 303-320 (1999)] we examined two principal features of heterogeneous photocatalysis that demanded scrutiny: (i) description of photocatalysis and (ii) description of process efficiencies. For the latter we proposed a protocol relative photonic efficiency which could subsequently be converted to quantum yields. A difficulty in expressing a quantum yield in heterogeneous photochemistry is the very nature of the system, either solid/liquid or solid/gas, which places severe restrictions on measurement of the photon flow absorbed by the light harvesting component, herein the photocatalyst TiO2, owing to non-negligible scattering by the particulates. It was imperative therefore to examine the extent of this problem. Extinction and absorption spectra of TiO2 dispersions were determined at low titania loadings by normal absorption spectroscopy and by an integrated sphere method, respectively, to assess the extent of light scattering. The method is compared to the one reported by Grela et al. [J. Phys. Chem., 100, 16940 (1996)] who used a polynomial extrapolation of the light scattered in the visible region into the UV region where TiO2 absorbs significantly. This extrapolation underestimates the scattering component present in the extinction spectra, and will no doubt affect the accuracy of the quantum yield data. Further, we report additional details in assessing limiting photonic efficiencies and quantum yields in heterogeneous photocatalysis.

Experimental determination of luminescence quantum yields for ZnS-type phosphors

1970 ◽  
Vol 12 (1) ◽  
pp. 129-130
Author(s):  
U. Kh. Nymm ◽  
V. G. Plekhanov ◽  
I. Kh. Rammo
Keyword(s):  
Experimental Determination ◽  
Quantum Yields

Experimental determination of a state equation for dissipative granular gases

1999 ◽  
Vol 96 (6) ◽  
pp. 1111-1116 ◽  
Author(s):  
E. Falcon ◽  
S. Fauve ◽  
C. Laroche
Keyword(s):  
Experimental Determination ◽  
State Equation ◽  
Granular Gases
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