Special Issue "Photocatalytic Hydrogen Evolution"

A special issue of Catalysts (ISSN 2073-4344). This special issue belongs to the section "Photocatalysis".

Deadline for manuscript submissions: 30 April 2019

Special Issue Editors

Guest Editor
Prof. Dr. Misook Kang

Department of Chemistry, College of Natural Sciences, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
Website | E-Mail
Interests: photocatalysis; thermocatalysis; hydrogen; CO2 reduction; photovoltaics; battery
Guest Editor
Dr. Vignesh Kumaravel

Department of Environmental Science, Institute of Technology Sligo, Ash lane, Co. Sligo, Ireland
Website | E-Mail
Interests: photocatalysis; hydrogen; CO2 reduction; hydrophobicity

Special Issue Information

Dear Colleagues,

Energy crises and global warming are key challenges for researchers in order to develop a sustainable society for the future. Solar energy conversion is a remarkable, clean, and sustainable solution to nullify the effects of fossil fuels. The findings of photocatalytic hydrogen production (PCHP) by Fujishima and Honda realized that “water will be the coal for the future”. Hydrogen is a carbon-free clean fuel with a high specific energy of combustion. Titanium oxide (TiO2), graphitic-carbon nitride (g-C3N4) and cadmium sulfide (CdS) are three pillars of water splitting photocatalysts owing to their superior electronic and optical properties. Tremendous research efforts have been made in recent years to fabricate visible or solar-light, active photocatalysts. The main aim of this Special Issue is to present the significant features of oxide, sulfide, and carbon based photocatalysts for cost-effective hydrogen production.

We are pleased to invite submissions in the form of original research articles, communications, and short reviews that reflect key findings of semiconductor photocatalysts in the following topics: UV or visible or solar light assisted hydrogen production; photocatalytic hydrogen evolution (PCHE) using seawater/industrial waste water; and photocatalytic reactor design for efficient hydrogen production.

This Special Issue is not limited to the above-mentioned topics, but also welcome manuscripts on novel photocatalytic materials, systems, or mechanisms for hydrogen production.

Prof. Dr. Misook Kang
Dr. Vignesh Kumaravel
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Catalysts is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • PCHE under UV or visible or simulated solar light
  • PCHE from seawater/ industrial waste water
  • PCHE without electron-donors
  • PCHE with in-situ electron donors
  • Mechanistic aspects of PCHE

Published Papers (5 papers)

View options order results:
result details:
Displaying articles 1-5
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Photocatalytic Hydrogen Production: Role of Sacrificial Reagents on the Activity of Oxide, Carbon, and Sulfide Catalysts
Catalysts 2019, 9(3), 276; https://doi.org/10.3390/catal9030276
Received: 15 February 2019 / Accepted: 11 March 2019 / Published: 18 March 2019
PDF Full-text (2989 KB) | HTML Full-text | XML Full-text
Abstract
Photocatalytic water splitting is a sustainable technology for the production of clean fuel in terms of hydrogen (H2). In the present study, hydrogen (H2) production efficiency of three promising photocatalysts (titania (TiO2-P25), graphitic carbon nitride (g [...] Read more.
Photocatalytic water splitting is a sustainable technology for the production of clean fuel in terms of hydrogen (H2). In the present study, hydrogen (H2) production efficiency of three promising photocatalysts (titania (TiO2-P25), graphitic carbon nitride (g-C3N4), and cadmium sulfide (CdS)) was evaluated in detail using various sacrificial agents. The effect of most commonly used sacrificial agents in the recent years, such as methanol, ethanol, isopropanol, ethylene glycol, glycerol, lactic acid, glucose, sodium sulfide, sodium sulfite, sodium sulfide/sodium sulfite mixture, and triethanolamine, were evaluated on TiO2-P25, g-C3N4, and CdS. H2 production experiments were carried out under simulated solar light irradiation in an immersion type photo-reactor. All the experiments were performed without any noble metal co-catalyst. Moreover, photolysis experiments were executed to study the H2 generation in the absence of a catalyst. The results were discussed specifically in terms of chemical reactions, pH of the reaction medium, hydroxyl groups, alpha hydrogen, and carbon chain length of sacrificial agents. The results revealed that glucose and glycerol are the most suitable sacrificial agents for an oxide photocatalyst. Triethanolamine is the ideal sacrificial agent for carbon and sulfide photocatalyst. A remarkable amount of H2 was produced from the photolysis of sodium sulfide and sodium sulfide/sodium sulfite mixture without any photocatalyst. The findings of this study would be highly beneficial for the selection of sacrificial agents for a particular photocatalyst. Full article
(This article belongs to the Special Issue Photocatalytic Hydrogen Evolution)
Figures

Figure 1

Open AccessArticle In-Situ Synthesis of Nb2O5/g-C3N4 Heterostructures as Highly Efficient Photocatalysts for Molecular H2 Evolution under Solar Illumination
Catalysts 2019, 9(2), 169; https://doi.org/10.3390/catal9020169
Received: 7 January 2019 / Revised: 23 January 2019 / Accepted: 7 February 2019 / Published: 11 February 2019
PDF Full-text (5315 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
This work focuses on the synthesis of heterostructures with compatible band positions and a favourable surface area for the efficient photocatalytic production of molecular hydrogen (H2). In particular, 3-dimensional Nb2O5/g-C3N4 heterostructures with suitable band [...] Read more.
This work focuses on the synthesis of heterostructures with compatible band positions and a favourable surface area for the efficient photocatalytic production of molecular hydrogen (H2). In particular, 3-dimensional Nb2O5/g-C3N4 heterostructures with suitable band positions and high surface area have been synthesized employing a hydrothermal method. The combination of a Nb2O5 with a low charge carrier recombination rate and a g-C3N4 exhibiting high visible light absorption resulted in remarkable photocatalytic activity under simulated solar irradiation in the presence of various hole scavengers (triethanolamine (TEOA) and methanol). The following aspects of the novel material have been studied systematically: the influence of different molar ratios of Nb2O5 to g-C3N4 on the heterostructure properties, the role of the employed hole scavengers, and the impact of the co-catalyst and the charge carrier densities affecting the band alignment. The separation/transfer efficiency of the photogenerated electron-hole pairs is found to increase significantly as compared to that of pure Nb2O5 and g-C3N4, respectively, with the highest molecular H2 production of 110 mmol/g·h being obtained for 10 wt % of g-C3N4 over Nb2O5 as compared with that of g-C3N4 (33.46 mmol/g·h) and Nb2O5 (41.20 mmol/g·h). This enhanced photocatalytic activity is attributed to a sufficient interfacial interaction thus favouring the fast photogeneration of electron-hole pairs at the Nb2O5/g-C3N4 interface through a direct Z-scheme. Full article
(This article belongs to the Special Issue Photocatalytic Hydrogen Evolution)
Figures

Graphical abstract

Open AccessArticle Band Gap Modulation of Tantalum(V) Perovskite Semiconductors by Anion Control
Catalysts 2019, 9(2), 161; https://doi.org/10.3390/catal9020161
Received: 11 January 2019 / Revised: 1 February 2019 / Accepted: 3 February 2019 / Published: 7 February 2019
PDF Full-text (1901 KB) | HTML Full-text | XML Full-text
Abstract
Band gap magnitudes and valence band energies of Ta5+ containing simple perovskites (BaTaO2N, SrTaO2N, CaTaO2N, KTaO3, NaTaO3, and TaO2F) were studied by diffuse reflection absorbance measurements, density-functional theoretical calculations, and [...] Read more.
Band gap magnitudes and valence band energies of Ta5+ containing simple perovskites (BaTaO2N, SrTaO2N, CaTaO2N, KTaO3, NaTaO3, and TaO2F) were studied by diffuse reflection absorbance measurements, density-functional theoretical calculations, and X-ray photoelectron spectroscopy. As a universal trend, the oxynitrides have wider valence bands and narrower band gaps than isostructural oxides, owing to the N 2p contribution to the electronic structure. Visible light-driven water splitting was achieved by using Pt-loaded CaTaO2N, together with a sacrificial agent CH3OH. Full article
(This article belongs to the Special Issue Photocatalytic Hydrogen Evolution)
Figures

Figure 1

Open AccessArticle Enhancement of Hydrogen Productions by Accelerating Electron-Transfers of Sulfur Defects in the [email protected]2 Heterojunction Photocatalysts
Catalysts 2019, 9(1), 41; https://doi.org/10.3390/catal9010041
Received: 29 November 2018 / Revised: 22 December 2018 / Accepted: 28 December 2018 / Published: 4 January 2019
PDF Full-text (3675 KB) | HTML Full-text | XML Full-text
Abstract
CuS and CuGaS2 heterojunction catalysts were used to improve hydrogen production performance by photo splitting of methanol aqueous solution in the visible region in this study. CuGaS2, which is a chalcogenide structure, can form structural defects to promote separation of [...] Read more.
CuS and CuGaS2 heterojunction catalysts were used to improve hydrogen production performance by photo splitting of methanol aqueous solution in the visible region in this study. CuGaS2, which is a chalcogenide structure, can form structural defects to promote separation of electrons and holes and improve visible light absorbing ability. The optimum catalytic activity of CuGaS2 was investigated by varying the heterojunction ratio of CuGaS2 with CuS. Physicochemical properties of CuS, CuGaS2 and [email protected]2 nanoparticles were confirmed by X-ray diffraction, ultraviolet visible spectroscopy, high-resolution transmission electron microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. Compared with pure CuS, the hydrogen production performance of CuGaS2 doped with Ga dopant was improved by methanol photolysis, and the photoactivity of the heterogeneous [email protected]2 catalyst was increased remarkably. Moreover, the [email protected]2 catalyst produced 3250 μmol of hydrogen through photolysis of aqueous methanol solution under 10 h UV light irradiation. According to the intensity modulated photovoltage spectroscopy (IMVS) results, the high photoactivity of the [email protected]2 catalyst is attributed to the inhibition of recombination between electron-hole pairs, accelerating electron-transfer by acting as a trap site at the interface between CuGaS2 structural defects and the heterojunction. Full article
(This article belongs to the Special Issue Photocatalytic Hydrogen Evolution)
Figures

Graphical abstract

Review

Jump to: Research

Open AccessReview Photocatalytic Hydrogen Evolution via Water Splitting: A Short Review
Catalysts 2018, 8(12), 655; https://doi.org/10.3390/catal8120655
Received: 23 October 2018 / Revised: 6 December 2018 / Accepted: 8 December 2018 / Published: 12 December 2018
PDF Full-text (5693 KB) | HTML Full-text | XML Full-text
Abstract
Photocatalytic H2 generation via water splitting is increasingly gaining attention as a viable alternative for improving the performance of H2 production for solar energy conversion. Many methods were developed to enhance photocatalyst efficiency, primarily by modifying its morphology, crystallization, and electrical [...] Read more.
Photocatalytic H2 generation via water splitting is increasingly gaining attention as a viable alternative for improving the performance of H2 production for solar energy conversion. Many methods were developed to enhance photocatalyst efficiency, primarily by modifying its morphology, crystallization, and electrical properties. Here, we summarize recent achievements in the synthesis and application of various photocatalysts. The rational design of novel photocatalysts was achieved using various strategies, and the applications of novel materials for H2 production are displayed herein. Meanwhile, the challenges and prospects for the future development of H2-producing photocatalysts are also summarized. Full article
(This article belongs to the Special Issue Photocatalytic Hydrogen Evolution)
Figures

Figure 1

Catalysts EISSN 2073-4344 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top