Opening and blocking the inner-pores of halloysite

Aggregation and dispersion behaviours of halloysite nanotubes (HNTs) were influenced by pH. The meso-and micro-porosity of halloysitewere determined by N-2 gas physisorption. The blocking and opening of halloysite nanotube pores with acid, neutral, and base treatment were detected in a micro-and mesoporous matrix of tunable porosity. The inner pores of HNTs were opened with base treatment, but were closed with acid or neutral treatment.