While green and blue hydrogen claim most of the limelight, turquoise hydrogen is emerging as an interesting alternative. It sidesteps the chicken-and-egg challenge of CO2 transport and storage infrastructure availability, and it can capitalize on high-value markets for pure carbon to reach commercial maturity.
Although the technology is still at a relatively low technology readiness level, the economic case is compelling, and the pathway to profitable commercial deployment is clear. The following popular science article provides further details.