Query: Hydrogen production from semiconductor solar energy

Candidate papers:

abstract: Abstract Photocatalytic hydrogen production from water splitting is a promising approach to develop sustainable renewable energy resources and limits the global warming simultaneously. Despite the significant efforts have been dedicated for the synthesis of semiconductor materials, key challenge persists is lower quantum efficiency of a photocatalyst due to charge carrier recombination and inability of utilizing full spectrum of solar light irradiation. In this review, recent developments in binary semiconductor materials and their application for photocatalytic water splitting toward hydrogen production are systematically discoursed. In the main stream, fundamentals and thermodynamic for photocatalytic water splitting and selection of photo catalysts has been presented. Developments in the binary photocatalysts and their efficiency enhancements though surface sensitization, surface plasmon resonance (SPR) effect, Schoktty barrier and electrons mediation toward enhanced hydrogen production has been deliberated. Different modification approaches including band engineering, coupling of semiconductor catalysts, construction of heterojunction, Z scheme formation and step type photocatalytic systems are also discussed. The binary semiconductor materials such as TiO2, g C3N4, ZnO, ZnS, Fe2O3, CdS, WO3, rGO, V2O5 and AgX (Cl, Br and I) are systematically disclosed. In addition, role of sacrificial reagents for efficient photocatalysis through reforming and hole scavenger are elaborated. Finally, future perspectives for photocatalytic water splitting towards renewable hydrogen production have been suggested.
author_names: Muhammad Tahir

Sehar Tasleem

Beenish Tahir
title: Recent development in band engineering of binary semiconductor materials for solar driven photocatalytic hydrogen production
year: 2020

abstract: Hydrogen is the ideal fuel for the future because it is clean, energy efficient, and abundant in nature. While various technologies can be used to generate hydrogen, only some of them can be considered environmentally friendly. Recently, solar hydrogen generated via photocatalytic water splitting has attracted tremendous attention and has been extensively studied because of its great potential for low cost and clean hydrogen production. This paper gives a comprehensive review of the development of photocatalytic water splitting for generating hydrogen, particularly under visible light irradiation. The topics covered include an introduction of hydrogen production technologies, a review of photocatalytic water splitting over titania and non titania based photocatalysts, a discussion of the types of photocatalytic water splitting approaches, and a conclusion for the current challenges and future prospects of photocatalytic water splitting. Based on the literatures reported here, the development of highly stable visible light active photocatalytic materials, and the design of efficient, low cost photoreactor systems are the key for the advancement of solar hydrogen production via photocatalytic water splitting in the future.
author_names: C H Liao

Chao-Wei Huang

Jeffrey Chi-Sheng Wu
title: Hydrogen Production from Semiconductor based Photocatalysis via Water Splitting
year: 2012

abstract: CuO is a promising but unstable photocathode in solar water splitting. Herein, a flexible CuO photocathode is prepared and its degradation mechanisms and stabilization strategies have been discussed. Briefly, we find alkali environment and low light intensity are the critical factors in the stabilization of the CuO photocathode. For practical usage, a composite semiconductor layer, composed of TiO2, La2O3 and NiO, is deposited on the CuO photocathode, which is proved to be effective for enhancing the stabilization of the CuO photocathode. 100% of the photocurrent density has been retained after 20 minutes of continuous illumination. The optimized stable photocurrent density is measured as 0.3 mA cm 2 at 0.5 VRHE.
author_names: Yang Li

Kai Luo
title: Flexible cupric oxide photocathode with enhanced stability for renewable hydrogen energy production from solar water splitting
year: 2019

abstract: P water splitting provides an attractive method to convert the abundant solar energy into sustainable and clean hydrogen energy. The greatest challenge is how to develop efficient and stable photoelectrodes, including photoanodes and photocathodes. Comparing to the widely studied photoanodes, the photocathodes have been paid less attention due to the scarcity of suitable semiconductor candidates. Some available photocathodes derived from p type semiconductors such as single crystal Si, chalcogenide (e.g. CuInGaSe) are either not stable or too expensive to realize large scale application. Herein, a promising p type semiconductor, CuBi2O4, has been used to fabricate efficient photocathode. Moreover, combining the CuBi2O4 photocathode with well developed BiVO4 photoanode, it is able to demonstrate unbiased sunlight driven solar water splitting. CuBi2O4 electrodes were prepared with electrodeposited BiOI and copper acetylacetonate as precusor after heating in air at 450degC for 4 hours. The CuBi2O4 photocathode possesses a porous nano branch strucutre and showed a photocurrent of 0.95 mA/cm2 at 0.21 VRHE along with an onset potential at 1.1 VRHE in Sodium Phosphate ~pH 7) electrolyte. With the presence of electron scavengers, the photocurrent was further enhanced to 2.4 mA/cm2 at 0.48 VRHE. The incident photon to current efficiency showed a threshold at ca. 620 nm, suggesting a broad light harvesting range of the CuBi2O4 photocathode. Furthermore, the large onset potential of CuBi2O4 photocathode makes it feasible to realize unbiased photoelectrode water splitting when combined with suitable photoanode, such as BiVO4.
author_names: pSabiha Akter Monny Zhiliang Wang

Lianzhou Wangp
title: Semiconductor nanostructure engineering for solar hydrogen production
year: 2019

abstract: The efficiency of photoelectrochemical tandem cells is still limited by the availability of stable low band gap electrodes. In this work, we report a photocathode based on lithium doped copper(ii) oxide, a black p type semiconductor. Density functional theory calculations with a Hubbard U term show that low concentrations of Li (Li0.03Cu0.97O) lead to an upward shift of the valence band maximum that crosses the Fermi level and results in a p type semiconductor. Therefore, Li doping emerged as a suitable approach to manipulate the electronic structure of copper oxide based photocathodes. As this material class suffers from instability in water under operating conditions, the recorded photocurrents are repeatedly misinterpreted as hydrogen evolution evidence. We investigated the photocorrosion behavior of LixCu1 xO cathodes in detail and give the first mechanistic study of the fundamental physical process. The reduced copper oxide species were localized by electron energy loss spectroscopy mapping. Cu2O grows as distinct crystallites on the surface of LixCu1 xO instead of forming a dense layer. Additionally, there is no obvious Cu2O gradient inside the films, as Cu2O seems to form on all LixCu1 xO nanocrystals exposed to water. The application of a thin Ti0.8Nb0.2Ox coating by atomic layer deposition and the deposition of a platinum co catalyst increased the stability of LixCu1 xO against decomposition. These devices showed a stable hydrogen evolution for 15 minutes.
author_names: Jonathan Kampmann

Sophia B Betzler

Hamidreza Hajiyani

Sebastian Haringer

Michael Beetz

Tristan Philipp Harzer

Jurgen Kraus

Bettina V Lotsch

Christina Scheu

Rossitza Pentcheva

Dina Fattakhova-Rohlfing

Thomas Bein
title: How photocorrosion can trick you: a detailed study on low bandgap Li doped CuO photocathodes for solar hydrogen production.
venue: Nanoscale
year: 2020

abstract: Efficient solar energy conversion system for hydrogen production from water, solar hydrogen system, is one of most important technologies for genuinely sustainable development of the society in the world wide scale. However, there are many problems to breakthrough such as low solar to H2 efficiency (STH) high cost, low stability, etc in order to realize the system practically and economically. The solar hydrogen systems using semiconductors are mainly classified as follows; solar cell electrolysis system, semiconductor photoelectrode system, and photocatalyst system. There are various merits and demerits in each system. The solar cell electrolysis system is very efficient but is very high cost. The photocatalyst system is very simple and relatively low cost, but the efficiency is still very low. On the other hand, various semiconductor systems with high efficiency have been investigated. A high STH more than 10% was reported using non oxide semiconductor photoelectrodes such as InGaP, while the preparati.
author_names: Kazuhiro Sayama

Takeo Arai
title: Efficient Solar Energy Conversion Systems for Hydrogen Production from Water using Semiconductor Photoelectrodes and Photocatalysts
year: 2008

abstract: Abstract Photocatalytic hydrogen production is considered to be a promising solution to the global energy crisis and to environmental pollution caused by fossil fuel consumption. In the present study, a core/shell cadmium sulfide/zinc oxide (ZnO/CdS) semiconductor heterojunction photocatalyst is used with a cobalt salen molecular co catalyst for highly enhanced photocatalytic activity. CdS nanorods were synthesized using a simple solvothermal method and a ZnO shell was grown by a solution deposition method. Under optimum conditions, the system exhibited a H 2 evolution rate of 725 umol h 1 mg 1 with a turnover number of ~102,700 and excellent stability over 50 h in the presence of Na 2 S/Na 2 SO 3 as the electron donor under visible light. The highest apparent quantum yield of the system was 44% under monochromatic 420 nm light. The formation of ZnS during photocatalysis was proved due to surface dissolution of ZnO in alkaline sulfide solution. ZnS can enhance the photocatalytic activity of ZnO/CdS nanorods by providing increased charge transfer interfaces. The molecular cobalt co catalyst also contributed to the enhanced activity by accepting the photogenerated electrons from the semiconductor photosensitizer. The proposed mechanism suggests that the photogenerated electrons in CdS are transferred not only to ZnO but also to the molecular co catalysts, leading to highly improved photocatalytic activity for H 2 production.
author_names: Rana Muhammad Irfan

Daochuan Jiang

Zijun Sun

Lei Zhang

Shengsheng Cui

Pingwu Du
title: Incorporating a molecular co catalyst with a heterogeneous semiconductor heterojunction photocatalyst: Novel mechanism with two electron transfer pathways for enhanced solar hydrogen production
year: 2017

abstract: Abstract Water splitting technology directly stores solar energy into the chemical bonds of diatomic hydrogen to be used as a clean fuel without producing any unwanted side reactions, byproducts or environmentally polluting compounds. Semiconductor materials are needed for a photoelectrochemical (PEC) device to catalytically convert photons from sunlight into chemical energy. Materials implemented in a device for sustainable hydrogen production are required to be inexpensive, highly photo active, chemically stable, environmentally sustainable, and have a high solar to hydrogen conversion efficiency. Although many semiconductor composites and nanostructures have been examined, thus far, no material satisfies all criteria of an implementable photocatalyst and many materials do not show necessary energy conversion efficiency. Materials that depicted a high efficiency often rely on the ultraviolet portion of the solar spectrum, which does not contain enough energy for the industrial utilization of PEC water splitting technologies. Focusing on the use of the visible spectrum is promising for hydrogen production. Herein, recent advancements in the activity of visible light semiconductors are presented, including both platinum and non platinum group materials. This review touches on the latest developments in various synthesis schemes capable of achieving suitable water splitting compositions and architectures while highlighting the challenges being faced when designing visible light active water splitting photocatalysts. Interesting advancements in the use of nanostructures for designing the next generation of catalysts will be discussed. Also, for the proper comparison of catalytic efficiencies, it is important to establish terminology that can compare data across a magnitude of experimental conditions. A notable challenge associated with the catalysis is its stability or photocorrosion, which lacks established protocols. Promising future directions for designing next generation materials are discussed.
author_names: Sushil Kumar Saraswat

Dylan D Rodene

Ram B Gupta
title: Recent advancements in semiconductor materials for photoelectrochemical water splitting for hydrogen production using visible light
year: 2018

abstract: Abstract Green and efficient energy technologies are a key point where nanoscience could make a difference in the paradigm shift from fossil fuels to renewable sources. One attractive possibility is the utilization of solar energy to obtain electricity or chemical fuel based on the ability of semiconductor nanomaterials to function as photocatalysts promoting various oxidation and reduction reactions under sunlight. We report on a novel class of Bi based photocatalysts for hydrogen production via water splitting. A screening DFT investigation was performed on the Bi2(MO4)3 (M Cr, Mo, and W) systems. The Bi2(CrO4)3 system exhibits the smallest band gap energy, the highest dielectric constant, and the highest absorption in visible region among the other counterpart materials. Consequently, Bi2(CrO4)3 nanoparticles were synthesized via a simple one pot method at room temperature and characterized by XRD, XPS, DRS, FE SEM, HR TEM, and Raman spectroscopy. The as prepared yellow Bi2(CrO4)3 nanoparticles exhibited a direct band gap energy of 2.45 eV. The photoactivity of the as prepared Bi2(CrO4)3 nanoparticles was tested toward the photocatalytic hydrogen production, where reasonable rates of 522.44, 174.15, and 88.24 mmol/g/h were achieved under UV, AM 1.5, and visible irradiations, respectively in the absence of any hole scavengers. Those rates are higher than those reported for Bi based photocatalysts.
author_names: Mahmoud Hamza

Ayat N El-Shazly

Sarah A Tolba

Nageh K Allam
title: Novel Bi based photocatalysts with unprecedented visible light driven hydrogen production rate: Experimental and DFT insights
year: 2020

abstract: Abstract In this study, the hydrogen production performance of a reactor assisted by a solar pond by photoelectrochemical method is examined conceptually. The main components of the new integrated system are a solar pond, a photovoltaic panel (PV) and a hybrid chlor alkali reactor which consists of a semiconductor anot, photocathode and cation exchange membrane. The proposed system produces hydrogen via water splitting reaction and also yields the by products namely chlorine and sodium hydroxide while consumes saturated NaCl solution and pure water. In order to increase the efficiency of the reactor, the saturated hot NaCl solution at the heat storage zone (HSZ) of the solar pond is transferred to the anot section and the heated pure water by heat exchanger in the HSZ is transferred to cathode section. The photoelectrode releases electrons for hydrogen production with diminishing the power requirement from the PV panel that is used as a source of electrical energy for the electrolysis. The results confirm that the thermal performance of the solar pond plays a key role on the hydrogen production efficiency of the reactor.
author_names: Mehmet Karakilcik

Mustafa Erden

Muzeyyen Cilogullari

Ibrahim Dincer
title: Investigation of hydrogen production performance of a reactor assisted by a solar pond via photoelectrochemical process
year: 2018