Scalable Cathodic H2O2 Electrosynthesis using Cobalt-Coordinated Nanocellulose Electrocatalyst.

Converting hierarchical biomass structure into cutting-edge architecture of electrocatalysts can effectively relieve the extreme dependency of nonrenewable fossil-fuel-resources typically suffering from low cost-effectiveness, scarce supplies, and adverse environmental impacts. A cost-effective cobalt-coordinated nanocellulose (CNF) strategy is reported for realizing a high-performance 2e-ORR electrocatalysts through molecular engineering of hybrid ZIFs-CNF architecture. By a coordination and pyrolysis process, it generates substantial oxygen-capturing active sites within the typically oxygen-insulating cellulose, promoting O2 mass and electron transfer efficiency along the nanostructured Co3O4 anchored with CNF-based biochar. The Co-CNF electrocatalyst exhibits an exceptional H2O2 electrosynthesis efficiency of ≈510.58 mg L-1 cm-2 h-1 with an exceptional superiority over the existing biochar-, or fossil-fuel-derived electrocatalysts. The combination of the electrocatalysts with stainless steel mesh serving as a dual cathode can strongly decompose regular organic pollutants (up to 99.43% removal efficiency by 30 min), showing to be a desirable approach for clean environmental remediation with sustainability, ecological safety, and high-performance.

Hierarchical Bilayer Polyelectrolyte Ion Paper Conductor for Moisture-Induced Power Generation.

Harvesting energy from air water (atmospheric moisture) promises a sustainable self-powered system without any restrictions from specific environmental requirements (e.g., solar cells, hydroelectric, or thermoelectric devices). However, the present moisture-induced power devices traditionally generate intermittent or bursts of energy, especially for much lower current outputs (generally keeping at nA or µA levels) from the ambient environment, typically suffering from inferior ionic conductivity and poor hierarchical structure design for manipulating sustained air water and ion-charge transport. Here, we demonstrate a universal strategy to design a high-performance bilayer polyelectrolyte ion paper conductor for generating continuous electric power from ambient humidity. The generator can produce a continuous voltage of up to 0.74 V and also an exceptional current of 5.63 mA across a single 1.0 mm-thick ion paper conductor. We discover that the sandwiched LiCl-nanocellulose-engineered paper promises an ion-transport junction between the negatively and positively charged bilayer polyelectrolytes for application in MEGs with both high voltage and high current outputs. Moreover, we demonstrated the universality of this bilayer sandwich nanocellulose-salt engineering strategy with other anions and cations, exhibiting similar power generation ability, indicating that it could be the next generation of sustainable MEGs with low cost, easier operation, and high performance.

All-Printed Flexible Hygro-Thermoelectric Paper Generator.

The conversion of ubiquitous hygrothermal resources into renewable energy offers significant potential for cable-free, self-powered systems that can operate worldwide without regard to climatic or geographic limitations. Here, an all-printed flexible hygro-thermoelectric paper generator is demonstrated that uses bifunctional mobile ions and electrons to make the moist-diffusion effect, the Soret effect, and the Seebeck effect work synergistically. In the ordinary hygrothermal settings, it generates an unconventional hygro-thermoelectric output pattern and shows almost a dozen-fold increase in positive hygro-thermopower of 26.70 mV K-1 and also another negative hygro-thermopower of -15.71 mV K-1 compared to pure thermopower. A single paper generator can produce a giant 680 mV displaying typical cyclic sinusoidal waveform characters with volt-sized amplitudes. The ion-electron conductive ink is easily printable and consists primarily of a Bi2 Te3 /PEDOT:PSS thermoelectric matrix modulated with a hygroscopic glycerol that releases ion charges for moist-diffusion effect and Soret effect, as well as electron charges for Seebeck effect. The emerged hygro-thermoelectric harvesting strategy from surrounding hygrothermal resources offers a revolutionary approach to the next generation of hybrid energy with cost-efficiency, flexibility, and sustainability, and also enables large-scale roll-to-roll production.