Uniform　and　continuous　Al2O3　thin　films　were　prepared　by　the　chemical　liquid　deposition　(CLD)　method.　The　breakdown　field　strength　of　the　amorphous　CLD-Al2O3　film　is　1.74　MV/cm,　making　it　could　be　used　as　a　candidate　dielectric　film　for　electronic　devices.　It　was　further　proposed　to　use　the　CLD-Al2O3　film　as　an　electron　blocking　layer　in　a　triboelectric　nanogenerator　(TENG)　for　output　performances　enhancement.　Output　voltages　and　currents　of　about　200　V　and　9　mu　A　were　obtained,　respectively,　which　were　2.6　times　and　3　times,　respectively,　higher　than　TENG　device　without　an　Al2O3.　A　colloidal　condensation-based　procedure　controlled　by　adjusting　the　pH　value　of　the　solution　was　proposed　to　be　the　mechanism　of　CLD,　which　was　confirmed　by　the　Tyndall　effect　observed　in　the　growth　liquid.　The　results　indicated　that　the　CLD　could　serve　as　a　low-cost,　room　temperature,　nontoxic　and　facile　new　method　for　the　growth　of　functional　thin　films　for　semiconductor　device　applications.