Single-Atom Pd–N_(3)Sites on Carbon-Defi cient g-C_(3)N_(4)for Photocatalytic H_(2)Evolution

Photocatalytic hydrogen evolution is an attractive fi eld for future environment-friendly energy.However,fast recombination of photogenerated charges severely inhibits hydrogen effi ciency.Single-atom cocatalysts such as Pt have emerged as an eff ective method to enhance the photocatalytic activity by introduction of active sites and boosting charge separation with low-coordination environment.Herein,we demonstrated a new strategy to develop a highly active Pd single atom in carbondefi cient g-C_(3)N_(4)with a unique coordination.The single-atom Pd–N_(3)sites constructed by oil bath heating and photoreduction process were confi rmed by HADDF-STEM and XPS measurements.Introduction of single-atom Pd greatly improved the separation and transportation of charge carriers,leading to a longer lifespan for consequent reactions.The obtained singleatom Pd loaded on the carbon-defi cient g-C_(3)N_(4)showed excellent photocatalytic activity in hydrogen production with about 24 and 4 times higher activity than that of g-C_(3)N_(4)and nano-sized Pd on the same support,respectively.This work provides a new insight on the design of single-atom catalyst.

2D Nanomaterials for Effective Energy Scavenging

The development of a nation is deeply related to its energy consumption.2D nanomaterials have become a spotlight for energy harvesting applications from the small-scale of low-power electronics to a large-scale for industry-level applications,such as self-powered sensor devices,environmental monitoring,and large-scale power generation.Scientists from around the world are working to utilize their engrossing properties to overcome the challenges in material selection and fabrication technologies for compact energy scavenging devices to replace batteries and traditional power sources.In this review,the variety of techniques for scavenging energies from sustainable sources such as solar,air,waste heat,and surrounding mechanical forces are discussed that exploit the fascinating properties of 2D nanomaterials.In addition,practical applications of these fabricated power generating devices and their performance as an alternative to conventional power supplies are discussed with the future pertinence to solve the energy problems in various fields and applications.

Polydopamine nanolayer assisted internal photo-deposition of CdS nanocrystals for stable cosensitized photoanode

Hydrogen evolution via photo-electro-chemical(PEC)co-catalysis is potential for solving energy crisis and environmental issues.The rapidly advances of fabrication and broad applications of polydopamine(PDA)and its derivatives have drawn intense attentions in recent years.Herein,an ultrathin PDA coating with nanometer accuracy was conformally grown on TiO_(2) nanotube arrays(NTAs)via electrochemical polymerization,in which the polymer provided a platform for further photoinduced assembly of CdS nanocrystals in the embedded mode.The optimized CdS@PDA/TiO_(2) NTAs hierarchical heterostructure as photoanode gave an excellent PEC performance and exhibited outstanding stability under light irradiation.The photocurrent density was heightened to 5.48 mA·cm^(–2),which was beneficial to H_(2) evolution with a rate of 20μmol·h^(–1)·cm^(–2).The improvement of PEC activity was ascribed to co-photosensitization,optimized carriers transfer,and transport route arised from CdS embedding,resulting to provide a persistent driving force for charge separation based on secure heterojunction of CdS/TiO_(2) glued by PDA.The improvement of PEC stability was due to the inhibition of CdS photocorrosion covered by PDA shelter.This advance boded well for the development of PEC field founded on multifunctional PDA.