i²Cool, a technology-based start-up incubated by the CityU HK Tech 300 programme, aims to promote novel, energy-free, environmentally friendly passive radiative cooling paint (patented in Hong Kong) for energy-saving and decarbonisation to achieve net-zero buildings. The self-developed, high-performance paint features an edge in solar reflection and thermal emissions, resulting in a significant sub-ambient cooling effect, without the need for electricity or ozone-depleting refrigerants. We will collaborate with different parties and organisations in the building, energy and paint industries to effectively demonstrate and promote our paint products. We will offer continuous product and business upgrades to maintain our technical competence and business sustainability. The ultimate goal of i²Cool is to have a remarkable environmental and social impact, mitigate the energy shortage and climate change problems, and facilitate the overall sustainable development and economic growth of China, while achieving carbon neutrality.