scholarly journals How Light-Harvesting Semiconductors Can Alter the Bias of Reversible Electrocatalysts in Favor of H2 Production and CO2 Reduction

2013 ◽  
Vol 135 (40) ◽  
pp. 15026-15032 ◽  
Author(s):  
Andreas Bachmeier ◽  
Vincent C. C. Wang ◽  
Thomas W. Woolerton ◽  
Sophie Bell ◽  
Juan C. Fontecilla-Camps ◽  
...  
Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3052
Author(s):  
Hilmar Guzmán ◽  
Daniela Roldán ◽  
Adriano Sacco ◽  
Micaela Castellino ◽  
Marco Fontana ◽  
...  

Inspired by the knowledge of the thermocatalytic CO2 reduction process, novel nanocrystalline CuZnAl-oxide based catalysts with pyramidal mesoporous structures are here proposed for the CO2 electrochemical reduction under ambient conditions. The XPS analyses revealed that the co-presence of ZnO and Al2O3 into the Cu-based catalyst stabilize the CuO crystalline structure and introduce basic sites on the ternary as-synthesized catalyst. In contrast, the as-prepared CuZn- and Cu-based materials contain a higher amount of superficial Cu0 and Cu1+ species. The CuZnAl-catalyst exhibited enhanced catalytic performance for the CO and H2 production, reaching a Faradaic efficiency (FE) towards syngas of almost 95% at −0.89 V vs. RHE and a remarkable current density of up to 90 mA cm−2 for the CO2 reduction at −2.4 V vs. RHE. The physico-chemical characterizations confirmed that the pyramidal mesoporous structure of this material, which is constituted by a high pore volume and small CuO crystals, plays a fundamental role in its low diffusional mass-transfer resistance. The CO-productivity on the CuZnAl-catalyst increased at more negative applied potentials, leading to the production of syngas with a tunable H2/CO ratio (from 2 to 7), depending on the applied potential. These results pave the way to substitute state-of-the-art noble metals (e.g., Ag, Au) with this abundant and cost-effective catalyst to produce syngas. Moreover, the post-reaction analyses demonstrated the stabilization of Cu2O species, avoiding its complete reduction to Cu0 under the CO2 electroreduction conditions.


2019 ◽  
Vol 48 (5) ◽  
pp. 1672-1679 ◽  
Author(s):  
Zhenyu Xin ◽  
Lei Lu ◽  
Bing Wang ◽  
Xiaohui Wang ◽  
Kai Zhu ◽  
...  

Improvement of light harvesting and reaction kinetics is of great importance for achieving efficient solar-driven CO2 reduction.


Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 680 ◽  
Author(s):  
Sakar ◽  
Prakash ◽  
Do

Photocatalysis is a multifunctional phenomenon that can be employed for energy applications such as H2 production, CO2 reduction into fuels, and environmental applications such as pollutant degradations, antibacterial disinfection, etc. In this direction, it is not an exaggerated fact that TiO2 is blooming in the field of photocatalysis, which is largely explored for various photocatalytic applications. The deeper understanding of TiO2 photocatalysis has led to the design of new photocatalytic materials with multiple functionalities. Accordingly, this paper exclusively reviews the recent developments in the modification of TiO2 photocatalyst towards the understanding of its photocatalytic mechanisms. These modifications generally involve the physical and chemical changes in TiO2 such as anisotropic structuring and integration with other metal oxides, plasmonic materials, carbon-based materials, etc. Such modifications essentially lead to the changes in the energy structure of TiO2 that largely boosts up the photocatalytic process via enhancing the band structure alignments, visible light absorption, carrier separation, and transportation in the system. For instance, the ability to align the band structure in TiO2 makes it suitable for multiple photocatalytic processes such as degradation of various pollutants, H2 production, CO2 conversion, etc. For these reasons, TiO2 can be realized as a prototypical photocatalyst, which paves ways to develop new photocatalytic materials in the field. In this context, this review paper sheds light into the emerging trends in TiO2 in terms of its modifications towards multifunctional photocatalytic applications.


Catalysts ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 40
Author(s):  
José C. Conesa

Sulfides are frequently used as photocatalysts, since they absorb visible light better than many oxides. They have the disadvantage of being more easily photocorroded. This occurs mostly in oxidizing conditions; therefore, they are commonly used instead in reduction processes, such as CO2 reduction to fuels or H2 production. Here a summary will be presented of a number of sulfides used in several photocatalytic processes; where appropriate, some recent reviews will be presented of their behaviour. Results obtained in recent years by our group using some octahedral sulfides will be shown, showing how to determine their wavelength-dependent photocatalytic activities, checking their mechanisms in some cases, and verifying how they can be modified to extend their wavelength range of activity. It will be shown here as well how using photocatalytic or photoelectrochemical setups, by combining some enzymes with these sulfides, allows achieving the photo-splitting of water into H2 and O2, thus constituting a scheme of artificial photosynthesis.


Author(s):  
Yiping Mo ◽  
Chun Wang ◽  
Longfei Xiao ◽  
Wenxing Chen ◽  
Wangyang Lu

Photocatalytic conversion of CO2 into value-added chemicals is considered to be a promising strategy to capture greenhouse gas as well as produce energy. The exploration of efficient and stable photocatalysts...


2016 ◽  
Vol 69 (1) ◽  
pp. 2
Author(s):  
Goudappagouda ◽  
Vivek Chandrakant Wakchaure ◽  
Kayaramkodath Chandran Ranjeesh ◽  
Sukumaran Santhosh Babu

Supramolecular assembly of molecules leading to gelation of large amount of solvents is always a fascinating topic of research. In the very recent past, the exciting developments have marked hydrogels as intriguing materials with excellent features. Hydrogel scaffolds enable the accommodation of organic and/or inorganic guest materials to deliver diverse applications. Hydrogels have been exploited to generate soft materials with mechanical anisotropy, tunable rigidity, self-healing properties, as well as photocatalytic capabilities towards H2 production. Remarkably, the combination of a photocatalyst and a light-harvesting system in the gel matrix provides a unique means to photocatalytic H2 production. The biomimetic applications of hydrogels have also generated much attraction due to their potential demonstrations. The diverse applications underline the significance of such a soft gel medium to reach the final goal. Herein, important reports pertaining to the use of hydrogels as an effective way to generate advanced materials for biomimetic and energy-related issues are discussed.


2018 ◽  
Vol 47 (16) ◽  
pp. 5652-5659 ◽  
Author(s):  
Yong-Jun Yuan ◽  
Gaoliang Fang ◽  
Daqin Chen ◽  
Yanwei Huang ◽  
Ling-Xia Yang ◽  
...  

High light harvesting efficiency CuInS2 quantum dots/TiO2/MoS2 composite photocatalysts were prepared for visible-light-driven photocatalytic H2 production.


2019 ◽  
Vol 30 (20) ◽  
pp. 18506-18518 ◽  
Author(s):  
Ali M. Huerta-Flores ◽  
E. Luévano-Hipólito ◽  
Leticia M. Torres-Martínez ◽  
A. Torres-Sánchez

Sign in / Sign up

Export Citation Format

Share Document