In Figure (c), we can observe a significant increase in the number of papers regarding TiC starting from 2019. The publication count almost tripled from 2019 to 2020 and doubled from 2020 to 2021. However, in 2022, there was a decrease in the percentage of publications. We notice that in 2009, publications about TiC accounted for 3% of the total literature on CO 2 RR (Figure (b)), but from 2009 onwards to 2014, we did not find any further mentions of TiC in the articles included in our corpus. However, our corpus comprises only 33 papers published in 2009, as can be seen in Figure . This value of 3.03% accounts for a single publication. Therefore, we can say that TiC has indeed recently gained attention in CO 2 RR. Regarding NaBH, from Figure (d) we can observe that there is a decreasing trend in the number of publications about this compound, starting from 2014, when it accounted for 2.76% of the papers. The percentage steadily declined to 0.52% in 2018, and since then, has remained relatively constant, representing around 0.50% of the papers published. It is interesting to note that most of the articles employing NaBH for direct CO 2 reduction were published between 2014 and 2016, with a higher concentration in 2014, indicating a specific trend during that period, which may explain the highest score in that particular year.