Kent State University

About: Kent State University is a education organization based out in Kent, Ohio, United States. It is known for research contribution in the topics: Liquid crystal & Population. The organization has 10897 authors who have published 24607 publications receiving 720309 citations. The organization is also known as: Kent State & KSU.

Characterization of semiconductor photocatalysts

Abstract: The long-standing popularity of semiconductor photocatalysis due to its great potential in a variety of applications has resulted in the creation of numerous semiconductor photocatalysts, which stimulated the development of various characterization methods. This review aims to summarize the main characterization methods for assessing the most important properties of semiconductor photocatalysts, including their chemical composition (elemental composition, and chemical state/structure), physical properties (physical structure, crystallographic properties, optical absorption, charge dynamics, defects, and colloidal and thermal stability), and band structure (band gap, band edges/band edge offsets, and Fermi level). The discussion on each of these methods starts with a concise presentation of its fundamentals followed by carefully selected examples. At the end, a chart correlating the properties of a semiconductor with its potential characterization methods as well as outlook are provided. Overall, the aim of this review article is to help materials chemists and physicists, particularly students, in selecting suitable techniques for the characterization of semiconductor photocatalysts and potentially other relevant materials.

Electrocatalytic Refinery for Sustainable Production of Fuels and Chemicals

Abstract: Compared to modern fossil-fuel-based refineries, the emerging electrocatalytic refinery (e-refinery) is a more sustainable and environmentally benign strategy to convert renewable feedstocks and energy sources into transportable fuels and value-added chemicals. A crucial step in conducting e-refinery processes is the development of appropriate reactions and optimal electrocatalysts for efficient cleavage and formation of chemical bonds. However, compared to well-studied primary reactions (e.g., O2 reduction, water splitting), the mechanistic aspects and materials design for emerging complex reactions are yet to be settled. To address this challenge, herein, we first present fundamentals of heterogeneous electrocatalysis and some primary reactions, and then implement these to establish the framework of e-refinery by coupling in situ generated intermediates (integrated reactions) or products (tandem reactions). We also present a set of materials design principles and strategies to efficiently manipulate the reaction intermediates and pathways.

Interpreting ecological diversity indices applied to terminal restriction fragment length polymorphism data: insights from simulated microbial communities.

Abstract: Ecological diversity indices are frequently applied to molecular profiling methods, such as terminal restriction fragment length polymorphism (T-RFLP), in order to compare diversity among microbial communities. We performed simulations to determine whether diversity indices calculated from T-RFLP profiles could reflect the true diversity of the underlying communities despite potential analytical artifacts. These include multiple taxa generating the same terminal restriction fragment (TRF) and rare TRFs being excluded by a relative abundance (fluorescence) threshold. True community diversity was simulated using the lognormal species abundance distribution. Simulated T-RFLP profiles were generated by assigning each species a TRF size based on an empirical or modeled TRF size distribution. With a typical threshold (1%), the only consistently useful relationship was between Smith and Wilson evenness applied to T-RFLP data (TRF-Evar) and true Shannon diversity (H′), with correlations between 0.71 and 0.81. TRF-H′ and true H′ were well correlated in the simulations using the lowest number of species, but this correlation declined substantially in simulations using greater numbers of species, to the point where TRF-H′ cannot be considered a useful statistic. The relationships between TRF diversity indices and true indices were sensitive to the relative abundance threshold, with greatly improved correlations observed using a 0.1% threshold, which was investigated for comparative purposes but is not possible to consistently achieve with current technology. In general, the use of diversity indices on T-RFLP data provides inaccurate estimates of true diversity in microbial communities (with the possible exception of TRF-Evar). We suggest that, where significant differences in T-RFLP diversity indices were found in previous work, these should be reinterpreted as a reflection of differences in community composition rather than a true difference in community diversity.