**4. Carbon capture and utilization**

Carbon capture and storage (CCS) technologies suffer till now from economic and technical limitations for large-scale employment such as the huge capital investment, shortage of geological storage sites, and high leakage rates of CO2 . Carbon capture and utilization (CCU) strategy, however, has emerged as a prospective alternative to CCS aiming to turn the CO2 emissions into relevant products such as fuels and chemicals. Both of the technologies target capturing anthropogenic CO2 emissions before being released to the environment, but they differ in the final destination where CCS aims at long-term storage, while CCU at conversions into useful products. CCU presents a set of advantages over CCS, namely the reduction of costs by synthesis of valuable products and the investment of CO2 as an available, nontoxic, and "renewable" resource being constantly emitted. Nonetheless, CCU can be only a short-lived solution, which delays the release of CO2 to later stages. Another important aspect that raises strong concerns in the large-scale application of both CCU and CCS is to ensure that the mitigation of the climate change is not achieved at the expense of other environmental issues [10, 11].

Carbon dioxide is indeed an extremely valuable molecule that can be utilized in diverse beneficial ways, as illustrated in **Figure 1** and detailed herein.
