S型异质结CO_(2)还原光催化剂

Photocatalytic CO_(2) reduction to solar fuels attracts great interest due to the growing fossil fuel shortage and global warming. Developing high-efficiency photocatalyst is the key for the solar fuel production ~(1,2). TiO_(2), as an inert, nontoxic and earth-abundant semiconductor, has been widely used for photocatalytic CO_(2) reduction.

一种乳酸菌-金属有机框架复合物用于强化肿瘤乏氧光动力和免疫治疗

开发长期有效的癌症治疗技术仍然是科研工作者和临床医生面临的重要任务.厌氧型乳酸菌(LAB)具有天然的乏氧倾向性,可自发富集在缺氧的肿瘤微环境中.金属有机框架(MOF)是一类独特的纳米材料,其中的ZIF-67可以自发分解过氧化氢产氧,且析氧能力可被光照增强.然而,LAB或MOF单独应用于肿瘤治疗的效果并不令人满意.在本文中,我们制备了一种MOF修饰的乳酸菌制剂,用以在缺氧性肿瘤中局部产生活性氧(ROS)助力光动力治疗,同时精准诱导宿主肿瘤免疫.这些细菌表面被ZIF-67纳米材料修饰(LAB@ZIF-67),经体内循环后富集在肿瘤微环境中.细菌表面的ZIF-67可以被CT-26细胞吸收,并且在光照后检测到细胞内快速生成ROS.体内实验表明,该细菌复合物可通过光动力疗法消灭肿瘤,同时诱导肿瘤特异的炎性反应,招募巨噬细胞和T细胞实现肿瘤的免疫治疗.此类材料-细菌复合物为今后研发肿瘤主动靶向药物和癌症免疫疗法提供了新思路.

Fully depleted vdW heterojunction based high performance photovoltaic photodetector

Van der Waals(vdW)heterojunctions,with their unique electronic and optoelectronic properties,have become promising candidates for photodetector applications.Amplifying the contribution of the depletion region in vdW heterojunction,which would enhance both of the collection efficiency and speed of the photogenerated carriers,presents an effective strategy for achieving high performance vdW heterojunction photodetectors.Herein,a fully depleted vdW heterojunction photodetector is built on two-dimensional(2D)semiconductor materials(GaTe and InSe)layered on a pattered bottom electrode in vertical structure,in which the generation and motion of carriers are exclusively achieved in the depletion region.Attributed to the intrinsic built-in electric field,the elimination of series resistance and the depletion region confinement of carriers,the as-fabricated photodetector exhibits prominent photovoltaic properties with a high open-circuit voltage of 0.465 V,as well as photoresponse characteristics with outstanding responsivity,detectivity and photoresponse speed of 63.7 A/W,3.88×10^(13)Jones,and 32.7 ms respectively.The overall performance of this fully depleted GaTe/InSe vdW heterojunctions photodetectors are ranking high among the top level of 2D materials based photodetectors.It indicates the device architecture can provide new opportunities for the fabrication of high-performance photodetectors.

Enhanced Photocatalytic H_(2)-production Activity of CdS Nanoflower using Single Atom Pt and Graphene Quantum Dot as Dual Cocatalysts

Single-atom catalysts have high catalytic activity due to their unique quantum size effects and optimal atom utilization.Herein,visi-ble-light-responsive photocatalysts were designed by coupling CdS with graphene quantum dots(GQDs)and platinum single atoms(PtSAs).GQDs and PtSAs were successively loaded on ultrathin CdS nanosheets through freeze-drying and in-situ photocatalytic reduction.The synergistic effect between PtSAs and GQDs results in superior photocatalytic activity with a hydrogen production rate of 13488μmol h^(-1)g^(-1)as well as the maximum apparent quantum efficiency(AQE)of 35.5%in lactic acid aqueous solution,which is 62 times higher than that of pristine CdS(213μmol g^(-1)h^(-1)).The energy conversion efficiency is ca.13.05%.As a photosensitizer and an electron reservoir,GQDs can not only extend the light response of CdS to the visible-light region(400-800 nm),but also promotes the separation of photoinduced electron-hole pairs.Meanwhile,PtSAs,with unique electronic and geometric features,can provide more efficient proton reduction sites.This finding provides an effective strategy to remarkably improve the photocatalytic H_(2) production performance.

TiO2 nanosheets with exposed {001} facets for photocatalytic applications

TiO2 nanosheets with highly reactive {001} facets （{001}-TiO2） have attracted great attention in the fields of science and technology because of their unique properties. In recent years, many efforts have been made to synthesize {001}-TiO2 and to explore their applications in photocatalysis. In this review, we summarize the recent progress in preparing {001}-TiO2 using different techniques such as hydrothermal, solvothermal, alcohothermal, chemical vapor deposition （CVD）, and sol gel-based techniques. Furthermore, the enhanced efficiency of {001}-TiO2 by modification of carbon materials, surface deposition of transition metals, and non-metal doping is reviewed. Then, the applications of {001}-TiOR-based photocatalysts in the degradation of organic dyes, hydrogen evolution, carbon dioxide （CO2） reduction, bacterial disinfection, and dye-sensitized solar cells are summarized. We believe this entire review on TiO2 nanosheets with {001] facets can further inspire researchers in associated fields.

2D-ultrathin MXene/DOXjade platform for iron chelation chemo-photothermal therapy

An increased demand for iron is a hallmark of cancer cells and is thought necessary to promote high cell proliferation,tumor progression and metastasis.This makes iron metabolism an attractive therapeutic target.Unfortunately,current iron-based therapeutic strategies often lack effectiveness and can elicit off-target toxicities.We report here a dual-therapeutic prodrug,DOXjade,that allows for iron chelation chemo-photothermal cancer therapy.This prodrug takes advantage of the clinically approved iron chelator deferasirox(ExJade®)and the topoisomerase 2 inhibitor,doxorubicin(DOX).Loading DOXjade onto ultrathin 2D Ti_(3)C_(2) MXene nanosheets produces a construct,Ti_(3)C_(2)-PVP@DOXjade,that allows the iron chelation and chemotherapeutic functions of DOXjade to be photo-activated at the tumor sites,while potentiating a robust photothermal effect with photothermal conversion efficiencies of up to 40%.Antitumor mechanistic investigations reveal that upon activation,Ti_(3)C_(2)-PVP@DOXjade serves to promote apoptotic cell death and downregulate the iron depletion-induced iron transferrin receptor(TfR).A tumor pH-responsive iron chelation/photothermal/chemotherapy antitumor effect was achieved both in vitro and in vivo.The results of this study highlight what may constitute a promising iron chelation-based phototherapeutic approach to cancer therapy.

Ionized cocatalyst to promote CO_(2) photoreduction activity over core-triple-shell ZnO hollow spheres

Solar-driven CO_(2) conversion into value-added chemicals is a sustainable solution to achieve carbon neutrality.Yu’s group have recently reported Mn,C-codoped ZnO coretriple-shell hollow spheres(CTSHSs)for efficient CO_(2) reduction.The Mn ions,with switchable valence states,functioned as"ionized cocatalyst"to promote the CO_(2) adsorption。