Nanofluid had been widely used in heat transfer applications due to its better thermophysical properties. However, nanofluid had a problem in the stability of nanoparticles suspended in the based fluid. Several ways had been done to increase the stability of nanofluids including using surfactants. The purpose of this review is to uncover the stability and heat transfer performance of nanofluid using surfactants. A systematic review was used to collect the related articles for this review. This review shows the mechanism of two types of surfactants that had been used which are ionic and non-ionic. Furthermore, the stability of nanofluid is very important to enhance the thermal performance of nanofluid. The recommendations are highlighted to study the optimum amount of surfactant for respective nanofluids.

Nanocellulose defines as cellulosic materials in the nanometer range with at least one dimension. Nanocellulose is classified into three classes which are bacterial nanocellulose (BNC), cellulose nanofibrils (CNF), and cellulose nanocrystalline (CNC). Nanofluids had been widely been used in heat transfer applications because nanofluids are proven to have better thermal conductivity and enhance heat transfer performance compared with base fluid. However, liquid with suspended particles tends to destabilize, and sediments. Therefore, this study will uncover the effect of surfactant on the nanocellulose and its thermophysical properties. CNC with 0.1vol%, 0.5vol%, 0.9vol%, and 1.3vol% and Triton X-100 were used in this experiment. From the sedimentation observation after two weeks, there were no obvious agglomeration and sedimentation of CNC in the samples with surfactant compare with no surfactant. Furthermore, UV–vis spectroscopy analysis showed that samples with Triton X-100 have lower absorbance drop compare with no surfactant. This was due to the steric stabilization achieve for samples using Triton X-100. For thermal conductivity analysis, The highest reading of thermal conductivity was 1.224W/m.K for 0.5vol% at 40°C. Furthermore, the effective thermal conductivity achieves for 0.5vol% at 40°C was 1.301 compared with distilled water.