Table 1: Summary of different techniques used for carbon nanomaterial dispersion in cementitious matrix and resulting improvement in microstructure and mechanical properties.

Type and concentration of nanomaterialDispersion techniqueaImprovement in micro-structure and mechanical propertiesResearchers and reference

MWCNT, 1.0 wt.%UltrasonicationTotal porosity and surface area decreased by 16% and 23% Nochaiya and Chaipanich [107]

CNT, 1.0 wt.%, and fly ash cementUltrasonicationCompressive strength improved by 10%Chaipanich et al. [120]

MWCNT, 0.5 wt.%Functionalization with HNO3/H2SO4 mixture and direct mixing with cementCompressive and flexural strength improved by 19% and 25%, total porosity reduced by 64%, and pores with diameter >50 nm reduced by 82%Li et al. [101]

MWCNT, 0.5 wt.%Solvent (acetone) and ultrasonicationCompressive strength improved by 11% and 17% for pristine and annealed CNTsMusso et al. [112]

Short MWCNT, 0.2 wt.%Ultrasonication and superplasticizer Flexural strength and ductility improved by 269% and 81%Al-Rub et al. [109]

MWCNT, 0.08 wt.%Ultrasonication and surfactant Young′s modulus and flexural strength improved by 45% and 25%Konsta-Gdoutos et al. [81]

CNF, 0.048 wt.%Ultrasonication at optimum conditions and surfactantFlexural strength and Young′s modulus improved by 50% and 75%Metaxa et al. [110]

MWCNT, 0.2 wt.%Magnetic stirring, ultrasonication, and surfactant (NaDC)Flexural and compressive strength improved by 35.4% and 29.5%Luo et al. [83]

MWCNT, 0.5 wt.%Magnetic stirring, ultrasonication, and polycarboxylate admixtureCompressive strength improved by 25%Collins et al. [90]

MWCNT, 0.045 wt.%Carboxylic functionalization, ultrasonication, and polyacrylic acid polymer Compressive strength improved by 50%Cwirzen et al. [86]

Hybrid CNT-cement particleCNT growth onto cement particlesCompressive strength improved more than 2 timesNasibulin et al. [104]

CNT (0.02 wt.%) and NMK (6 wt.%)Dry mixing with cementCompressive strength improved by 11% than mortar containing NMKMorsy et al. [121]

CNF (0.048 wt.%) and PVA micro-fibres (0.54 wt.%)Ultrasonication and surfactantFlexural strength, Young′s modulus, and toughness improved by 50%, 84%, and 33 timesMetaxa et al. [82]

CNF (0.5 wt.%) and short carbon fibresAcetone, ultrasonication, and surfactantLoad carrying capacity and failure strain improved by 54% and 44%Hunashyal et al. [126]

The techniques for preparing aqueous dispersion of carbon nanomaterials are only provided here; subsequent mixing with cement mortar is performed using a standard mixer.