Solar energy is an eco-conscious substitute, for solar energy absorption and subsequent light-to-heat conversion, light-absorbing materials require broad-spectrum light absorption capabilities. Herein, we present the fabrication of broadband light-absorbing polypyrrole-carboxylated carbon nanotube membranes via a facile electrochemical deposition route. By manipulating electrochemical deposition time, the structure of the membranes was tailored, resulting in enhanced absorption, achieving over 98.95 % across the entire solar spectrum. The membranes demonstrated exemplary thermal efficacy and insensitivity to incident angles in photothermal conversion, the membranes facilitated a notable 12 °C temperature elevation within a simulated greenhouse compared to ambient conditions. Thus, these membranes exhibit considerable potential for widespread application in photothermal conversion and greenhouse technology.