## 4 Conclusions  
In conclusion, the research on enhanced gypsum boards incorporating activated carbon composites and phase change materials for advanced thermal energy storage and electromagnetic interference shielding properties has yielded significant insights and promising outcomes. The encapsulation of RT18 HC on AC derived from spent coffee showed no leaching of the PCM component and a high RT18 HC loading of \(\sim\)120.9 wt%. The successful incorporation of RT18 HC@AC composites into gypsum boards has demonstrated notable improvements in thermal energy storage capabilities. At the same time, the incorporation of these composite additives into gypsum boards can improve the mechanical properties of the gypsum board. At lower concentrations of RT18 HC@AC (up to 10% w.t. ), a positive correlation is evident, while at higher concentrations, mechanical degradation becomes apparent, concluding that the optimal content of the additive for gypsum boards is 10% w.t. RT18 HC@AC. The investigation into EMI shielding properties has shown that the RT18 HC@-activated carbon composites play crucial roles in attenuating electromagnetic interference. The composite material exhibits promising EMI shielding effectiveness, opening avenues for applications in electronics, telecommunications, and other industries where EMI mitigation is imperative. In addition, the gypsum board with a higher RT18 HC content demonstrated an ability to sustain a lower indoor room temperature for an extended  
Figure 12: Curves from thermal performance measurements for gypsum board samples with 10 and 30% RT18 HC@AC loadings in comparison with the reference gypsum board GB. duration. This dual functionality makes enhanced gypsum boards multifaceted solutions for modern construction and technological advancements. In summary, this research highlights the significance of using enhanced gypsum boards with activated carbon composites and PCMs as a promising solution for addressing the dual challenges of advanced thermal energy storage and electromagnetic interference shielding. The positive outcomes pave the way for practical applications and future innovations in the field of construction materials and technology. The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/micro4010005/s1](https://www.mdpi.com/article/10.3390/micro4010005/s1)]([https://www.mdpi.com/article/10.3390/micro4010005/s1](https://www.mdpi.com/article/10.3390/micro4010005/s1)), Table S1: Density of reference gypsum board and composite gypsum boards; Table S2: Thermal conductivity (k), thermal effusivity (e), and specific heat capacity (Cp) of reference gypsum board and composite boards GB/RT18 HC@AC; Table S3. Maximum load (Fmax), absorbed energy (Ea), and percentage increment of Ea (I) for the gypsum boards with varying % w.t. contents of RT18 HC@AC additive. Figure S1. Pictures from the custom-made environmental chamber. (a) The chamber during the measurements; (b,c) the internal area of the chamber. Figure S2: Force-displacement plots, obtained from impact resistance tests for gypsum boards with varying % w.t. contents of RT18 HC@AC additive. Conceptualization, M.A.K. and G.K.; methodology, M.A.K., G.K., S.A. and C.E.S. ; formal analysis, C.G., K.C.V., M.A.K., G.K., Z.V. and R.I.; investigation, C.G., K.C.V., Z.V. and A.N. ; resources, M.A.K., G.K. and A.S.P. ; data curation, M.A.K., G.K., S.A., Z.V., C.G., K.C.V., M.B., A.N., A.S.P., C.E.S. and R.I.; writing--original draft preparation, M.B. and M.A.K. ; writing--review and editing, M.A.K., G.K. and M.B. ; supervision, M.A.K. and G.K.; project administration, M.A.K. and G.K.; funding acquisition, M.A.K. and G.K; validation, S.A., C.E.S. and R.I. All authors have read and agreed to the published version of the manuscript. This work was co-financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH--CREATE--INNOVATE (acronym: SEMI-WEB; project code: T2 EDK-02073).