Fluorescent carbon dots(CDs) are admirable nanomaterials due to their superior optical properties and low cost.However,regulation of the emission colors in CDs for lighting device still remains a challenge.In this wor...Fluorescent carbon dots(CDs) are admirable nanomaterials due to their superior optical properties and low cost.However,regulation of the emission colors in CDs for lighting device still remains a challenge.In this work,we developed a green hydrothermal method to obtain three emission colors of CDs using L-tyrosine(for blue CDs),o-phenylendiamine(for green CDs) and L-tyrosine/o-phenylendiamine mixture(for orange-red CDs).These CDs possess good water dispersibility,strong emission with high quantum yields,and excellent photostability.Furthermore,the resulting CDs were dispersed in polyvinyl alcohol(PVA) matrix to yield solid state films,where the self-quenching effect in solid state was effectively avoided.A full-color light-emitting diode was fabricated by packing the CDs-PVA composites on the top of a UV-chip,which have superior potential applications in CDs-based solid-state lighting system.展开更多
Electrosynthesis of hydrogen peroxide(H2O_(2)),as a sustainable alternative to the anthraquinone oxidation method,provides the feasibility of directly generating H_(2)O_(2).Here,we report Cu-doped TiO_(2) as an effici...Electrosynthesis of hydrogen peroxide(H2O_(2)),as a sustainable alternative to the anthraquinone oxidation method,provides the feasibility of directly generating H_(2)O_(2).Here,we report Cu-doped TiO_(2) as an efficient electrocatalyst which exhibits the excellent two-electron oxygen reduction reaction(2e-ORR)performance with respect to the pristine TiO_(2).The Cu doping results in the distortion of TiO_(2) lattice and further forms a large number of oxygen vacancies and Ti^(3+).Such Cu-doped TiO_(2) exhibits a positive onset potential about 0.79 V and high H_(2)O_(2) selectivity about 91.2%.Moreover,it also shows a larger H_(2)O_(2) yield and good stability.Density functional theory(DFT)calculations reveal that Cu dopant not only improves the electrical conductivity of pristine TiO_(2) but reduces the*OOH adsorption energy of active sites,which is beneficial to promote subsequently 2e-ORR process.展开更多
基金finically supported by the National Key R&D Program of China (No. 2017YFE0118200)National Natural Science Foundation of China (Nos. 61671019, 51703002, and 51474003)+2 种基金Natural Science Foundation of Anhui Province, China (No. 1908085MB35)Natural Science Foundation for the Higher Education Institutions of Anhui Province of China (Nos. KJ2018A0040 and KJ2018A0067)Key Lab of Guang Dong Province for High Property and Functional Polymer Materials (No. 20170003)。
文摘Fluorescent carbon dots(CDs) are admirable nanomaterials due to their superior optical properties and low cost.However,regulation of the emission colors in CDs for lighting device still remains a challenge.In this work,we developed a green hydrothermal method to obtain three emission colors of CDs using L-tyrosine(for blue CDs),o-phenylendiamine(for green CDs) and L-tyrosine/o-phenylendiamine mixture(for orange-red CDs).These CDs possess good water dispersibility,strong emission with high quantum yields,and excellent photostability.Furthermore,the resulting CDs were dispersed in polyvinyl alcohol(PVA) matrix to yield solid state films,where the self-quenching effect in solid state was effectively avoided.A full-color light-emitting diode was fabricated by packing the CDs-PVA composites on the top of a UV-chip,which have superior potential applications in CDs-based solid-state lighting system.
基金This work was supported by the National Natural ScienceFoundation of China (No. 22072015).
文摘Electrosynthesis of hydrogen peroxide(H2O_(2)),as a sustainable alternative to the anthraquinone oxidation method,provides the feasibility of directly generating H_(2)O_(2).Here,we report Cu-doped TiO_(2) as an efficient electrocatalyst which exhibits the excellent two-electron oxygen reduction reaction(2e-ORR)performance with respect to the pristine TiO_(2).The Cu doping results in the distortion of TiO_(2) lattice and further forms a large number of oxygen vacancies and Ti^(3+).Such Cu-doped TiO_(2) exhibits a positive onset potential about 0.79 V and high H_(2)O_(2) selectivity about 91.2%.Moreover,it also shows a larger H_(2)O_(2) yield and good stability.Density functional theory(DFT)calculations reveal that Cu dopant not only improves the electrical conductivity of pristine TiO_(2) but reduces the*OOH adsorption energy of active sites,which is beneficial to promote subsequently 2e-ORR process.
