Groundbreaking Advancements in Net-Zero Technology: National Synchrotron Radiation Research Center's Green Hydrogen Research Featured in Science Magazine
2023/09/07
A transnational collaborative research team, comprising Jeng-Lung Chen, Assistant Scientist, Yu-Chun Chuang, Associate Scientist, and Chung-Kai Chang, Research Assistant from the National Synchrotron Radiation Research Center (NSRRC) under the purview of the National Science and Technology Council, in partnership with Dr. Lu-Ning Chen, Professor Gabor A. Somorjai, and Dr. Ji Su from the Lawrence Berkeley National Laboratory in California, USA, has dedicated three years to pioneering global advancements in the field of green hydrogen production. Their groundbreaking work centers around the development of a methane pyrolysis catalyst, known as the "nickel-molybdenum-bismuth liquid alloy (NiMo-Bi)," which exhibits high hydrogen production efficiency, excellent stability, and low energy consumption. This study explored the electrostatic charge distribution on the active nickel sites in the molten state, demonstrating the NiMo-Bi liquid alloy's capability to effectively mitigate the cage effect caused by bismuth. This mitigation facilitates the effective flow of methane to active nickel sites, resulting in efficient hydrogen generation. This outstanding discovery was published in the respected international journal Science on August 25, 2023, emerging as a pivotal driving force for advancing the transition to a net-zero future.
The U.S. research team initially integrated molybdenum into the nickel-bismuth catalyst, resulting in the creation of an innovative catalyst known as NiMo-Bi liquid alloy. Meanwhile, NSRRC scientists engineered an experimental setup tailored for in-situ high-temperature gas-phase reactions. Harnessing the capabilities of the "Quick X-ray Absorption Spectroscopy Beamline" and the "High Resolution Powder X-ray Diffraction Beamline" at the Taiwan Photon Source (TPS), the team validated the catalyst's efficacy by significantly lowering methane pyrolysis temperatures to values as low as 450 °C. They also showed that at an elevated temperature of 800 °C, the selectivity of converting methane into hydrogen reached 100%, maintaining this optimal level for a stable period of 120 hours. This achievement marks a nearly 37-fold improvement in hydrogen production efficiency compared to previous methods. Concurrently, the optimal pyrolysis temperature was significantly reduced from 1065 degrees Celsius to 800 degrees Celsius, resulting in a significant reduction in the energy requirements of the conversion process.
In recent years, hydrogen, often hailed as the 'fuel of the future,' has emerged as a promising source of carbon emission-free energy. Extensive international research and development efforts have been undertaken in the field of hydrogen energy technology. Nonetheless, a substantial portion of hydrogen production relies on the combustion of fossil fuels, followed by subsequent recombination with water vapor—an approach associated with notably high carbon emissions. An alternative involves introducing a catalyst into electrolyzers to facilitate the electrolysis of water into hydrogen and oxygen. However, this method requires substantial energy input at extremely high voltage levels and incurs high costs due to the expense of the catalyst, thus limiting its widespread application. A third approach involves the catalytic pyrolysis of methane to yield hydrogen. This method holds promise due to its concurrent generation of valuable carbon by-products like graphene, carbon nanotubes, and fullerenes. Consequently, this approach is evolving into a zero-carbon-emission hydrogen production technology with promising prospects for robust commercial development.
The results of this study confirm that the utilization of the NiMo-Bi liquid alloy catalyst leads to a considerable improvement in both the efficiency and stability of methane pyrolysis for hydrogen production. This breakthrough holds promise for advancing the development of hydrogen energy, offering increased efficacy and reduced costs. To examine the interactions within NiMo-Bi liquid alloys, the research team employed the quick X-ray absorption spectroscopy beamline for 'active site exploration' and 'coordination environment analysis'. Due to its exceptional sensitivity at the atomic level and impressively low detection threshold (down to one part per million), this experimental technique is well suited for investigating diverse aspects such as the oxidation states of metallic elements, the types and quantities of neighboring coordination elements, and the bond lengths and structural variations in neighboring atoms. The methodology enables the real-time observation of dynamic changes within the electronic and atomic structure of substances at the millisecond scale, thereby providing scientists with invaluable insights into the instantaneous behavior of catalysts during chemical reactions.
In pursuit of a deeper comprehension of the significant improvement in catalytic efficiency provided by NiMo-Bi liquid alloys, the research team carried out a multifaceted investigation. They utilized high-resolution powder diffraction beamlines to decipher the phase structure compositions inherent to NiMo-Bi liquid alloys and successfully verified the pivotal role of molybdenum atoms within NiMo-Bi catalysts. This was complemented by in-situ high-temperature experiments that provided insights into the structural phase transition exhibited by NiMo-Bi liquid alloys at varying temperatures. The beamline is characterized by its ultra-high diffraction resolution, rapid measurement capabilities, and applicability to a wide array of experimental samples. Enchanced by an integrated heating system, this technology enables the real-time monitoring of unconventional chemical reactions, including catalysis, heat treatment, and pyrolysis, as well as comprehensive and real-time structural analyses of energy materials.
Currently, the Taiwanese government is promoting the “Net Zero New Life initiative.” This effort involves coordinated collaboration across various ministries, public-private partnerships, and international alliances to advance research and development in five essential net-zero technology domains. The objective is to synergize and consolidate Taiwan's advantageous net-zero technologies, propelling domestic net-zero technologies and industries onto the global stage. With the long-term support of the National Science and Technology Council, NSRRC remains deeply committed to investing in green energy research and development, spanning hydrogen energy, solar power, lithium batteries, and supercapacitors. Moving forward, NSRRC is poised to continue aligning with the government's "2050 Net Zero Carbon Emission Goal." This commitment involves fostering key measurement techniques for net-zero advancements, encompassing clean new energy and emerging negative carbon technologies.
