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Objective To share our experience of percutaneous or transthoracic closure of atrial septal defect (ASD) and ventricular septal defect (VSD) supported by echocardiography guidance. Methods From December 2010 to September 2019, 54 patients of congenital heart disease (30 cases of isolated atrial septal defect, 24 cases of ventricular septal defect) were treated with surgical operation by occluder under guidance of echocardiography closed without cardiopulmonary bypass. Fourteen cases of ASD were performed device closure through a small right sternal margin thoracotomy incision at the forth intercostal space, 16 cases of ASD underwent percutaneous occlusion surgery, and 24 cases of VSD were closed through small incision under the xiphoid process. Results The operations were successful in the 24 cases of VSD. One of the cases with minimally incision ASD occlusion was displaced 7 hours after operation, the occluder was taken out and ASD was repaired under cardiopulmonary bypass in emergency. There were 13 cases of successful occlusion and 3 cases of failure in percutaneous ASD closure patients. Among three cases, 2 cases underwent ASD closed through transthoracic closure and 1 case underwent open surgery under cardiopulmonary bypass successfully. The 46 cases were followed up for 3-103 months, with an average of (21.3±16.2)months. No occluder displacement, shedding, significant residual shunt were observed. Conclusions Echocardiography-guided percutaneous atrial septal defect and ventricular septal defect is safe and effective without radiation and CPB. Percutaneous closure of atrial septal defect is suitable for children over 3 years. Atrial septal defect and ventricular septal defect occlusion through small thoracic incision is feasible and easy to operate in other healthcare institutions.

The appropriate and adjustable band structure and positive visible-light response enable the halide perovskite MAPbBr3 to be a promising photocatalyst for CO2 reduction. Considering the extremely poor water resistance and severe carrier complexation trends, rational design and control of steam stable MAPbBr3-based heterojunction nanocrystals to exploit their potential for photocatalytic CO2 reduction in steam is important while being a challenging topic. Here, an efficient MAPbBr3/Pb-MOF heterojunction photocatalyst is developed, ensuring in situ growth of Pb-MOF on the surface of the perovskite via a self-sacrificial template method, thus creating tightly connected interfaces to mitigate the sluggish charge transfer due to the discontinuous interfaces. The experimental results confirm that construction of MAPbBr3/Pb-MOF heterojunctions suppresses the recombination of photogenerated carriers. Meanwhile, the prepared MAPbBr3/Pb-MOF exhibits better steam stability, CO2 adsorption capacity, and higher separation efficiency of photogenerated carriers. The heterostructure enables the photocatalytic reduction of CO2 to CO at an excellent rate of 21.5 μmol g−1 under visible light irradiation, which is 4.8 times larger than that of pristine MAPbBr3. [ABSTRACT FROM AUTHOR]

Considering the large specific surface area, abundant active sites, and good electrical conductivity of metal–organic framework (MOF)-derived porous carbon materials, the rational design and fabrication of high-performance composite photocatalysts with tunable morphology and configuration are an extremely important and challenging topic to remove organic dyes from wastewater through the photocatalytic reaction. In this work, the ZnO–nano ZnO@porous carbon (ZnO–nZnO@PC) was in situ fabricated through the Ostwald ripening mechanism and facile pyrolysis process. The ZnO nanorods acted as a self-sacrificing template for achieving the tight binding of the ZnO–ZIF-8 core–shell structure with the thickness of the carbon layer regulated by controlling the amount of ligand, which was directly converted into nano-ZnO encapsulated with porous carbon materials through post-annealing process, improving the specific surface area, adsorption capacity of dye molecule, and transportation of charge carriers. Moreover, nano-ZnO in porous carbon shell further improves the photocatalytic activity. In addition, the piezoelectric effect produced by the internal polarized electric field of ZnO under the influence of ultrasonic energy provided by ultrasonic waves acts as a powerful driving force for the separation of photogenerated carriers, further enhancing the activity of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Iron being the second most abundant metal on the surface of the earth (5.1%), size-confined iron-based photocatalysts are of particular importance for solar energy conversion. Herein, a ternary Z-scheme g-C3N4/PPy/Fe2O3 heterostructure photocatalyst with PPy supporting and confining Fe2O3 was designed and fabricated for hydrogen production using a facile method. The small particle size of Fe2O3 (around 5 nm) improved the transport efficiency of charge carriers with the conductive PPy acting as a mediator, and the formation of the g-C3N4–Fe2O3 Z-scheme heterostructure dramatically facilitated the photocatalytic activity. Consequently, the optimal g-C3N4–PPy–Fe2O3 demonstrated an excellent photocatalytic hydrogen evolution activity, which was 120, 6.4 and 4.8 times larger than that of the pristine g-C3N4 and g-C3N4 singly loaded separately with PPy and Fe2O3, respectively, and exhibited considerable H2 and H2O2 production activity even in the absence of a sacrificial agent. [ABSTRACT FROM AUTHOR]