This research work reports on the potential of bagasse, a solid waste from sugar factories, to produce activated-carbon (AC) as an adsorbent. The activation was conducted under 500, 600, and 700 °C using steam as the activation agent to produce AC500, AC600, and AC700, respectively. The prepared-materials were characterized to understand their elemental content, surface morphology, thermal properties, functional groups identification, surface area, and pore size. AC700 provided the highest surface area of 592.36 m²/g and indicated the contribution of mesopores distributes along 1.5–8.0 nm of pore size. Therefore, an adsorption test was conducted with AC700 as adsorbent. The results show that methylene blue (MB) adsorption reached equilibrium after 30 min of adsorption time. The adsorption isotherm applied to a monolayer Langmuir isotherm was fitted by linearization, resulting in a constant R² of 0.999. The MB adsorption to AC700 favorably occurred, as proven by the Freundlich parameter 1/n of 0.881, which is less than 1. The Dubinin-Radushkevich isotherm confirmed that the adsorption proceeded through physical interaction with adsorption energy of 3.536 kJ/mol.

Graphene materials exhibit significant potential as electrocatalysts for the CO reduction reaction (CORR), a crucial process for mitigating greenhouse gas emissions. This study investigates the impact of boron (B) doping on the catalytic performance of graphene nanoclusters (GNCs) for CORR using density functional theory (DFT). Pristine GNC (C ₅₄ H ₁₈ ) and B‐doped GNC (C ₅₃ H ₁₈ B) were examined through the computational hydrogen electrode (CHE) model. The results demonstrate that B doping slightly enhances adsorption energy, with C ₅₃ H ₁₈ B exhibiting higher adsorption energy (−2.40 × 10 ⁻² eV) than C ₅₄ H ₁₈ (−0.79 × 10 ⁻² eV), indicating a modest improvement in interaction strength, which is attributed to the electron‐deficient sites introduced by the B atom, which strengthen CO‐surface interactions, as evidenced by a shorter distance of 3.62 Å in C ₅₃ H ₁₈ B compared to 3.92 Å in C ₅₄ H ₁₈ . Free energy diagrams for both models reveal that methanol formation follows the same pathway: *CO → *CHO → *CH ₂ O→ *OCH ₃ →CH ₃ OH. Notably, the overpotential required for spontaneous reaction is significantly lower for B‐GNC (0.89 V) than for the pristine GNC (1.50 V), indicating that B doping effectively enhances the electrocatalytic activity of GNCs for CORR. These findings highlight that B‐GNC is a promising candidate for metal‐free electrocatalysts with improved performance for sustainable COR applications.

This research conducted a molecular simulation of single N and double N/S doping into a carbon network. The simulation aimed to explain the effect of N and N/S doping, which was investigated experimentally by our previous research, and to prove the hypothesis that N and/or S replace a normal C site within the carbon crystal structure. Experimental data agree with the simulation result, as shown by the increasing ID/IG ratio in the Raman spectrum, which indicates defect formation after doping. Meanwhile, the XRD patterns of the doped carbon are similar to those of the undoped carbon. It suggests that the dopants N and/or S diffused and replaced the C atom from its normal site in the carbon crystal structure without forming new N and/or S-based compounds. The result is consistent with different dispersants investigated in this research, i.e., deionized water and ethanol. However, ethanol provided better dispersibility than water, resulting in a modified N/S carbon material with ethanol dispersant, NSCE, with a higher electrical conductivity of 23.74 x 10-1 Scm-1 than the N/S-modified carbon with water dispersion, NSCW, i.e., 5.97 x 10-1 Scm-1. The presence of defects increases the number of sites for charge carriers to migrate within the carbon network, making it a good electrode material for an LFP battery, with an initial charging capacity of 349.94 ± 79.04 mAh/g and an initial discharge capacity of 113.41 ± 12.59 mAh/g. The results reveal N/S-doped carbon as a sustainable candidate for lithium-ion batteries and other advanced energy storage technologies.