By Robert F. Service, Science.  Excerpt: Hydrogen is often touted as the future of green energy, and the allure is clear. When burned or run through a fuel cell, the fuel produces water as exhaust, not carbon dioxide (CO 2 ). It is energy-rich enough to drive semitrailer trucks, cargo ships, and other heavy-duty vehicles that are tough to power with batteries. And for many industrial processes requiring high-temperature reactions, such as fertilizer production and steel manufacturing, hydrogen is basically the only alternative to fossil fuels, says Kathy Ayers, a water electrolysis expert at Nel Hydrogen, a Norwegian electrolyzer producer. “Low-carbon hydrogen is absolutely essential if we are going to address the climate crisis.” ...According to the International Energy Agency, the world needs to churn out more than 300 million tons of green hydrogen annually if it is to have a shot at limiting global warming to 1.5°C by 2050. Yet today, operating green hydrogen plants, mostly in ...

By Darren Orf , Popular Mechanics.  Excerpt: ...a new electrode produced by the U.S. company Equatic can safely extract oxygen and hydrogen from seawater while leaving the salt, which usually produces deadly chlorine gas. As a bonus, this method uses direct air capture to remove carbon from the atmosphere. And the anodes are recyclable—they only need a recoating of catalysts (made from abundant materials) every three years. ...Producing hydrogen via seawater electrolysis has the nasty habit of also producing toxic chlorine gas, so current hydrogen production relies on pure water—a resource that’s becoming more and more precious as the world warms. Now, the carbon removal company Equatic—thanks to funding support from the U.S. Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-E)—has successfully developed “oxygen-selective anodes” (OSAs) that will hopefully help scale up hydrogen production via seawater  electrolysis . ...The process does produce acidic and ...