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Electrochemical CO 2 reduction (ECR) is a promising approach to realize carbon neutral and energy sustainability, which is still impeded by the low selectivity and activity for application. Defect engineering of electrocatalysts, especially oxygen vacancy introduction into metal oxide materials has been proved to be an effective strategy to satisfy thermodynamic condition and improve kinetics for ECR. Herein, we synthesize oxygen vacancy-enriched ZnO nanoparticle catalysts for efficient ECR through electrospinning technique using particular precursor. Characterizations reveal that the utilization of Zn(CH 3 COO) 2 precursor contributes to the generation of oxygen vacancies in ZnO catalysts which enhances CO 2 adsorption and stabilizes the intermediate. In a flow cell configuration, a current density of 150 mA cm−2 and a CO Faradic efficiency > 80% can be obtained for ZnO nanoparticle catalysts (p-ZnO-800), which is meaningful for industry. • The morphology of ZnO catalyst is affected by electrospinning precursor. • Reasonable selection or modification of metallic salt of electrospinning precursor is a promising method to obtain more defects. • Oxygen vacancies enhance the performance of CO 2 reduction. [ABSTRACT FROM AUTHOR]

Vegetation restoration affects the stability of soil organic carbon (SOC) by changing the composition of soil carbon pools, including active carbon (C a), the labile pool of SOC; slow carbon (C s), the physically stabilized pool of SOC; and resistant carbon (C r), the chemically stabilized pool of SOC. The aims of this study were to determine how SOC pools changed during restoration of a subtropical forest and to what extent vegetation characteristics and soil properties affected the changes in SOC pools. Soil samples were collected to 40 cm in four plant communities along a restoration chronosequence: scrub-grassland (4–5 years), shrubs (10–12 years), coniferous and broadleaved mixed forest (45–46 years), and evergreen broadleaved forest (90–91 years). Laboratory incubations were used to measure CO 2 production during SOC mineralization, and acid hydrolysis was used to measure C r. The CO 2 production and C r data were fitted to a three-component first-order kinetic model to determine the C a and C s. Pearson's correlations, stepwise multiple line regressions, and variation partitioning analysis were used to determine the key factors that affected SOC pools. The results showed that vegetation restoration increased the contents of SOC from 1.67 to 47.6 g kg−1, C a from 0.03 to 0.35 g kg−1, C s from 1.32 to 24.5 g kg−1, and C r from 0.33 to 22.8 g kg−1. During vegetation restoration, the increase in SOC was primarily due to carbon (C) stored in stable pools (i.e., C s or C r), and the portion of C r in total SOC increased markedly from 18.5 to 56.3%. Fine root biomass was the primary driver that controlled SOC pools during vegetation restoration. The C/N ratio of litter had a greater effect on C a and C s than that of other factors, whereas the soil clay content contributed secondarily to C r. The results suggest that vegetation restoration increases not only the amounts of SOC, C a , C s , and C r but also the stability of the SOC pool in subtropical soil. The relatively rapid increases in C s and C r following vegetation restoration played a crucial role in C sequestration. Therefore, strong measures to preserve natural forests and facilitate vegetation restoration should be the primary approach to increase long-term soil C sequestration in this region. • Soil organic carbon (SOC) content increased as vegetation restoration proceeded. • The increased SOC was mainly stored in the more stable carbon (C) pools. • Rapid increases in resistant C to SOC ratio played a crucial role in C stabilization. • Fine root biomass was the primary driver of the increased SOC pools with restoration. [ABSTRACT FROM AUTHOR]