[1] AUZEL F. Upconversion and anti-Stokes processes with f and d Ions in solids ［J］. Chem. Rev., 2004,104(1): 139-174.

[2] DOWNING E,HESSELINK L,RALSTON J,et al.. A three-color,solid-state,three-dimensional display ［J］. Science, 1996,273(5279): 1185-1189.

[3] SANDROCK T,SCHEIFE H,HEUMANN E,et al.. High-power continuous-wave upconversion fiber laser at room temperature ［J］. Opt. Lett., 1997,22(11): 808-810.

[4] OSTROWSKI A D,CHAN E M,GARGAS D J,et al.. Controlled synthesis and single-particle imaging of bright,sub-10 nm lanthanide-doped upconverting nanocrystals ［J］. ACS Nano, 2012,6(3): 2686-2692.

[5] YI G S,LU H C,ZHAO S Y,et al.. Synthesis,characterization,and biological application of size-controlled nanocrystalline NaYF4∶Yb, Er infrared-to-visible up-conversion phosphors ［J］. Nano Lett., 2004,4(11): 2191-2196.

[6] VAN DE RIJKE F,ZIJLMANS H,LI S,et al.. Up-converting phosphor reporters for nucleic acid microarrays ［J］. Nat. Biotechnol., 2001,19(3): 273-276.

[7] VENNERBERG D,LIN Z Q. Upconversion nanocrystals: synthesis, properties, assembly and applications ［J］. Sci. Adv. Mater., 2011,3(1): 26-40.

[8] ZHANG C,ZHOU H P,LIAO L Y,et al.. Luminescence modulation of ordered upconversion nanopatterns by a photochromic diarylethene: rewritable optical storage with nondestructive readout ［J］. Adv. Mater., 2010,22(5): 633-637.

[9] KIM W J,NYK M,PRASAD P N. Color-coded multilayer photopatterned microstructures using lanthanide(Ⅲ) ion co-doped NaYF4 nanoparticles with upconversion luminescence for possible applications in security ［J］. Nanotechnology, 2009,20(18): 185301-1-7.

[10] ZHANG G,DONG H,WANG D,et al.. Investigations on multi-photon emissions of Nd3+-sensitized core/shell nanoparticles ［J］. J. Rare Earths, 2017,35(1): 1-6.

[11] WANG X,ZHUANG J,PENG Q,et al.. A general strategy for nanocrystal synthesis ［J］. Nature, 2005,437(7055): 121-124.

[12] LIU Y X,WANG D S,SHI J X,et al.. Magnetic tuning of upconversion luminescence in lanthanide-doped bifunctional nanocrystals ［J］. Angew. Chem., 2013,125(16): 4462-4465.

[13] YU X F,LI M,XIE M Y,et al.. Dopant-controlled synthesis of water-soluble hexagonal NaYF4 nanorods with efficient upconversion fluorescence for multicolor bioimaging ［J］. Nano Res., 2010,3(1): 51-60.

[14] LIU D M,XU X X,DU Y,et al.. Three-dimensional controlled growth of monodisperse sub-50 nm heterogeneous nanocrystals ［J］. Nat. Commun., 2016,7: 10254-1-8.

[15] CARGNELLO M,GORDON T R,MURRAY C B. Solution-phase synthesis of titanium dioxide nanoparticles and nanocrystals ［J］. Chem. Rev., 2014,114(19): 9319-9345.

[16] DING M Y,ZHU F,MA D Y,et al.. KF-mediated controlled-synthesis of potassium ytterbium fluorides (doped with Er3+) with phase-dependent upconversion luminescence ［J］. CrystEngComm, 2015,17(37): 7182-7190.

[17] NIE L,SHEN Y X,ZHANG X,et al.. Selective synthesis of LaF3 and NaLaF4 nanocrystals via lanthanide ion doping ［J］. J. Mater. Chem. C, 2017,5(35): 9188-9193.

[18] 李洋洋,李大光,张丹,等. 小尺寸NaLuF4∶Yb3+/Tm3+纳米晶的生长及上转换发光 ［J］. 发光学报, 2018,39(6): 764-770.

    LI Y Y,LI D G,ZHANG D,et al.. Growth process and upconversion luminescence of NaLuF4∶Yb3+/Tm3+ nanocrystals ［J］. Chin. J. Lumin., 2018,39(6): 764-770. (in Chinese)

[19] WANG F,LIU X G. Multicolor tuning of lanthanide-doped nanoparticles by single wavelength excitation ［J］. Acc. Chem. Res., 2014,47(4): 1378-1385.

[20] SUN L D,WANG Y F,YAN C H. Paradigms and challenges for bioapplication of rare earth upconversion luminescent nanoparticles: small size and tunable emission/excitation spectra ［J］. Acc. Chem. Res., 2014,47(4): 1001-1009.

[21] DONG H,SUN L D,YAN C H. Basic understanding of the lanthanide related upconversion emissions ［J］. Nanoscale, 2013,5(13): 5703-5714.

[22] ZHANG Y W,SUN X,SI R,et al.. Single-crystalline and monodisperse LaF3 triangular nanoplates from a single-source precursor ［J］. J. Am. Chem. Soc., 2005,127(10): 3260-3261.

[23] BAI X,LI D,LIU Q,et al.. Concentration-controlled emission in LaF3∶Yb3+/Tm3+ nanocrystals: switching from UV to NIR regions ［J］. J. Mater. Chem., 2012,22(47): 24698-24704.

[24] SUYVER J F,GRIMM J,VAN VEEN M K,et al.. Upconversion spectroscopy and properties of NaYF4 doped with Er3+, Tm3+ and/or Yb3+ ［J］. J. Lumin., 2006,117(1): 1-12.

[25] GROEN C P,OSKAM A,KOVCS A. Theoretical study of mixed MLaX4(M=Na, K, Cs; X=F, Cl, Br, I) rare earth/alkali metal halide complexes ［J］. Inorg. Chem., 2003,42(3): 851-858.

[26] AHMAD S,PRAKASH G V,NAGARAJAN R. Hexagonally ordered KLaF4 host: phase-controlled synthesis and luminescence studies ［J］. Inorg. Chem., 2012,51(23): 12748-12754.

[27] RENERO-LECUNA C,MARTN-RODRGUEZ R,VALIENTE R,et al.. Origin of the high upconversion green luminescence efficiency in β-NaYF4∶2%Er3+,20%Yb3+ ［J］. Chem. Mater., 2011,23(15): 3442-3448.

[28] TYAGI N,REDDY A A,NAGARAJAN R. KLaF4∶Er an efficient upconversion phosphor ［J］. Opt. Mater., 2010,33(1): 42-47.

[29] DAS S,REDDY A A,AHMAD S,et al.. Synthesis and optical characterization of strong red light emitting KLaF4∶Eu3+ nanophosphors ［J］. Chem. Phys. Lett., 2011,508(1-3): 117-120.

[30] DU Y P,ZHANG Y W,SUN L D,et al.. Optically active uniform potassium and lithium rare earth fluoride nanocrystals derived from metal trifluroacetate precursors ［J］. Dalton. Trans., 2009,(40): 8574-8581.

[31] LIU R,TU D T,LIU Y S,et al.. Controlled synthesis and optical spectroscopy of lanthanide-doped KLaF4 nanocrystals ［J］. Nanoscale, 2012,4(15): 4485-4491.

[32] 赖文彬,周海芳,程树英,等. Er3+/Yb3+共掺KLaF4纳米晶的制备和上转换发光 ［J］. 发光学报, 2013,34(10): 1259-1263.

    LAI W B,ZHOU H F,CHENG S Y,et al.. Preparation and upconversion luminescence of Er3+/Yb3+ codoped KLaF4 nanocrystals ［J］. Chin. J. Lumin., 2013,34(10): 1259-1263. (in Chinese)

[33] MAI H X,ZHANG Y W,SI R,et al.. High-quality sodium rare-earth fluoride nanocrystals: controlled synthesis and optical properties ［J］. J. Am. Chem. Soc., 2006,128(19): 6426-6436.

[34] 王猛. 稀土上转换发光纳米材料的合成及应用 ［M］. 沈阳: 东北大学出版社, 2015.

    WANG M. Rare Earth Doped Upconversion Luminescent Nanomaterials: Synthesis and Applications ［M］. Shenyang: Dongbei University Press, 2015. (in Chinese)