China creates a new type of wood that provides solar energy even in the dark

The proposal represents a relevant change in the field of solar energy, traditionally limited by its direct dependence on solar radiation. Unlike conventional systems, which combine multiple layers and generate energy losses, this new solution converts the modified wood into a self-sufficient system. The advance is based on redesigning the internal structure of balsa wood at a nanometric scale. This material, known for its lightness, features aligned microscopic channels that facilitate both heat conduction and the integration of functional components inside. Advanced engineering in the structure of wood To achieve this behavior, scientists first eliminated lignin, the component that provides rigidity and color to wood. This process increased its porosity to over 93%, transforming it into a highly reactive network capable of housing new materials. Subsequently, the internal walls of these channels were coated with black phosphorene, a material with a high capacity to absorb light at different wavelengths. This choice made it possible to maximize the conversion of solar radiation into heat, although it presented a key problem: its degradation upon contact with air. To solve this, the researchers applied a protective layer based on tannic acid and iron ions, creating a network that acts as a shield against oxidation. As the authors explain, "Our work presents a scalable and environmentally friendly wood-based platform for the advanced collection of solar thermal energy." Thermal storage and electricity generation The system is completed with the incorporation of silver nanoparticles, which intensify light absorption, and with a surface modification that confers extreme hydrophobic properties. The result is a material with a contact angle of 153°, which prevents water from adhering to its surface. Stearic acid is introduced inside the structure, a compound capable of storing thermal energy when melting and releasing it when solidifying. This mechanism allows maintaining a temperature difference sufficient to power a thermoelectric generator even when the light source disappears. The tests carried out show that this material reaches a conversion efficiency of 91.27% and can generate up to 0.65 volts under standard solar irradiation conditions. In addition, it maintains its performance after more than 100 thermal cycles, which reinforces its viability as a sustainable energy solution. Future applications and challenges Beyond energy generation, this smart wood presents additional properties such as fire resistance, antimicrobial capacity and durability against adverse environmental conditions. These characteristics expand its potential in sectors such as construction or electronics. The tests carried out show that this material reaches a conversion efficiency of 91.27% and can generate up to 0.65 volts under standard solar irradiation conditions. In addition, it maintains its performance after more than 100 thermal cycles, which reinforces its viability as a sustainable energy solution. Future applications and challenges Beyond energy generation, this smart wood presents additional properties such as fire resistance, antimicrobial capacity and durability against adverse environmental conditions. These characteristics expand its potential in sectors such as construction or electronics. However, the researchers themselves warn that the next challenge will be to scale production and guarantee stable performance in real applications. If this challenge is overcome, this development could mark the beginning of a new generation of materials capable of autonomously capturing, storing and managing energy.