Holds Promise for Large-Scale Hydrogen Production, Desalination
Seawater is one of the most abundant resources on earth, offering promise both as a source of hydrogen – desirable as a source of clean energy – and of drinking water in arid climates. But even as water-splitting technologies capable of producing hydrogen from freshwater have become more effective, seawater has remained a challenge.
Researchers from the University of Houston have reported a significant breakthrough with a new oxygen evolution reaction catalyst that, combined with a hydrogen evolution reaction catalyst, achieved current densities capable of supporting industrial demands while requiring relatively low voltage to start seawater electrolysis.
Researchers say the device, composed of inexpensive non-noble metal nitrides, manages to avoid many of the obstacles that have limited earlier attempts to inexpensively produce hydrogen or safe drinking water from seawater. The work is described in Nature Communications.
Zhifeng Ren, director of the Texas Center for Superconductivity at UH and a corresponding author for the paper, said a major obstacle has been the lack of a catalyst that can effectively split seawater to produce hydrogen without also setting free ions of sodium, chlorine, calcium and other components of seawater, which once freed can settle on the catalyst and render it inactive. Chlorine ions are especially problematic, in part because chlorine requires just slightly higher voltage to free than is needed to free hydrogen.
The researchers tested the catalysts with seawater drawn from Galveston Bay off the Texas coast. Ren, M.D. Anderson Chair Professor of physics at UH, said it also would work with wastewater, providing another source of hydrogen from water that is otherwise unusable without costly treatment.
“Most people use clean freshwater to produce hydrogen by water splitting,” he said. “But the availability of clean freshwater is limited.”
To address the challenges, the researchers designed and synthesized a three-dimensional core-shell oxygen evolution reaction catalyst using transition metal-nitride, with nanoparticles made of a nickel-iron-nitride compound and nickel-molybdenum-nitride nanorods on porous nickel foam.
First author Luo Yu, a postdoctoral researcher at UH who is also affiliated with Central China Normal University, said the new oxygen evolution reaction catalyst was paired with a previously reported hydrogen evolution reaction catalyst of nickel-molybdenum-nitride nanorods.
The catalysts were integrated into a two-electrode alkaline electrolyzer, which can be powered by waste heat via a thermoelectric device or by an AA battery.
Cell voltages required to produce a current density of 100 milliamperes per square centimeter (a measure of current density, or mA cm-2) ranged from 1.564 V to 1.581 V.
The voltage is significant, Yu said, because while a voltage of at least 1.23 V is required to produce hydrogen, chlorine is produced at a voltage of 1.73 V, meaning the device had to be able to produce meaningful levels of current density with a voltage between the two levels.
The Latest on: Producing hydrogen from seawater
via Google News
The Latest on: Producing hydrogen from seawater
- Nanomaterial Extracts Hydrogen from Seawater for Clean Fuel Developmenton November 17, 2020 at 4:00 pm
Researchers have been working on ways for many years to extract hydrogen from seawater in a cost-effective way to produce an abundant source of clean fuel, to mixed results. Now a researcher at the ...
- Official Launch of Seawater Resources Technology Research Centeron November 17, 2020 at 1:22 am
UNIST held a ceremony to mark the official launch of the Seawater Resources Technology Research Center. This center is expected to ...
- Massive W.A. renewable hydrogen project signs up Copenhagen Infrastructure Partnerson November 15, 2020 at 8:32 pm
The goal of the project is to use these premium solar and wind energy resources, along with desalinated sea water, to produce renewable hydrogen for export to Asian markets, with an eye to Japan ...
- SunHydrogen Improves Hydrogen Production Device in Manufacturing Processon November 13, 2020 at 4:00 am
While the upgrade has caused a delay in production ... low-cost technology to make renewable hydrogen using sunlight and any source of water, including seawater and wastewater.
- SunHydrogen Improves Hydrogen Production Device in Manufacturing Processon November 13, 2020 at 2:35 am
While the upgrade has caused a delay in production, the outcome has been ... low-cost technology to make renewable hydrogen using sunlight and any source of water, including seawater and wastewater.
- Green gigawatts: could turbines supplant drillrigs for the US Gulf's energy transition?on November 11, 2020 at 1:30 pm
“And longer term, [we see] offshore renewable energy used to produce hydrogen from seawater.” Promise isn’t power production though. Wind speeds are measurably lower in the US Gulf than off the ...
- A renewable solution to keep cool in a warming worldon October 21, 2020 at 5:18 pm
A new IIASA-led study explored the pros and cons of seawater air-conditioning as an alternative cooling ... Given the recent interest in hydrogen production and hydrogen-based economies, SWAC could ...
- A renewable solution to keep cool in a warming worldon October 19, 2020 at 6:50 am
A new IIASA-led study explored the pros and cons of seawater air-conditioning as an ... Given the recent interest in hydrogen production and hydrogen-based economies, SWAC could even be combined ...
via Bing News