Scientists have developed a novel photocatalyst system for efficient syngas production from methane steam reforming, using solar energy and operating under atmospheric pressure. This technology marks a significant step towards sustainable syngas production and a post-carbon energy future.
A new solar-driven photocatalysis method for syngas production from methane steam reforming promises a more sustainable and efficient approach to syngas generation.
Recent research reveals a breakthrough in solar-driven syngas production, marking a potential transition to a post-carbon energy era. This innovative process involves the reforming of methane steam, a method that heats methane with steam in the presence of a catalyst to generate hydrogen and carbon monoxide, collectively known as syngas. Syngas is a valuable resource, serving as a versatile fuel.
Challenges in Methane Steam Reforming
Historically, achieving the necessary chemical reactions for methane steam reforming has been challenging. The process typically demands high temperatures between 700 and 1000 degrees CelsiusThe Celsius scale, also known as the centigrade scale, is a temperature scale named after the Swedish astronomer Anders Celsius. In the Celsius scale, 0 °C is the freezing point of water and 100 °C is the boiling point of water at 1 atm pressure.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>Celsius and pressures exceeding 20 bar. These demanding conditions have limited its practicality and efficiency.
Schematic for simultaneous adsorption/activation of CH4 and H2O by RhOx/GaN system based on density functional theory calculations. Credit: Li et al.
Photocatalysis: A Novel Approach
Baowen Zhou and his team introduce a pioneering photocatalysis platform that enables syngas production in a quartz chamber under atmospheric pressure illuminated by a 300 W Xenon lamp without any other energy inputs. The core of this technology is based on group III nitride nanowires enhanced with rhodium nanoclusters.
Mechanism of the Photocatalytic Process
Detailed theoretical calculations, microscopic examinations, and in situ spectroscopic measurements have demonstrated that the RhOx/GaN@InGaN nanowires are capable of activating both methane and water molecules under light exposure. Just add light, and methane is split into methyl anions and hydrogen speciesA species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>species, while water is split into hydrogen species and hydroxide. Subsequent reactions, facilitated by rhodium and gallium nitride, lead to the formation of syngas.
Efficiency and Stability of the New System
The effectiveness of this new method is evident, with a production rate of 8.1 mol syngas per gram of hydrogen and 10493 mol syngas per mol rhodium oxides observed over a 300-minute stability test. This represents a significant advancement in syngas production technology.
Reference: “A semiconducting hybrid of RhOx/GaN@InGaN for simultaneous activation of methane and water toward syngas by photocatalysis” by Dongke Li, Zewen Wu, Yixin Li, Xiaoxing Fan, S M Najib Hasan, Shamsul Arafin, Md Afjalur Rahman, Jinglin Li, Zhouzhou Wang, Tianqi Yu, Xianghua Kong, Lei Zhu, Sharif Md Sadaf and Baowen Zhou, 21 November 2023, PNAS Nexus.
DOI: 10.1093/pnasnexus/pgad347
Source: SciTechDaily
